Ford Escape Quiz
Powertrain

Diagnosis and Testing — Air/Fuel Ratio

In this manual: Powertrain
General Information — 26Chassis — 160Powertrain — 323Electrical — 356Body and Paint — 290
~49min read

Diagnostic Trouble Code (DTC) Chart

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).


Module Trouble Code Description Action
PCM P0030:00 HO2S Sensor Heater Control Circuit (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0030:00 HO2S Sensor Heater Control Circuit (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0036:00 HO2S Sensor Heater Control Circuit (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0037:00 HO2S Sensor Heater Control Circuit Low (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0038:00 HO2S Sensor Heater Control Circuit High (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0040:00 Oxygen Sensor Signals Crossed Bank 1 Sensor 1 / Bank 1 Sensor 2: No Sub Type Information GO to Pinpoint Test DZ
PCM P0041:00 Oxygen Sensor Signals Crossed: Bank 1 Sensor 2 / Bank 2 Sensor 2: No Sub Type Information GO to Pinpoint Test DW
PCM P0050:00 HO2S Sensor Heater Control Circuit (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0053:00 HO2S Sensor Heater Resistance (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0053:00 HO2S Sensor Heater Resistance (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0054:00 HO2S Sensor Heater Resistance (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0056:00 HO2S Sensor Heater Control Circuit (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0059:00 HO2S Sensor Heater Resistance (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0060:00 HO2S Sensor Heater Resistance (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P00D2:00 HO2S Sensor Heater Control Circuit Range/Performance (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0130:00 O2 Sensor Circuit (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0130:00 O2 Sensor Circuit (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0131:00 O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0131:00 O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0132:00 O2 Sensor Circuit High Voltage (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0132:00 O2 Sensor Circuit High Voltage (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0133:00 O2 Sensor Circuit Slow Response (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0133:00 O2 Sensor Circuit Slow Response (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0134:00 O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0134:00 O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0135:00 O2 Sensor Heater Circuit (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DW
PCM P0135:00 O2 Sensor Heater Circuit (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0136:00 O2 Sensor Circuit (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0137:00 O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0138:00 O2 Sensor Circuit High Voltage (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0139:00 O2 Sensor Circuit Slow Response (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P013A:00 O2 Sensor Slow Response - Rich to Lean (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P013B:00 O2 Sensor Slow Response - Lean to Rich (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P013C:00 O2 Sensor Slow Response - Rich to Lean (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P013E:00 O2 Sensor Delayed Response - Rich to Lean (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0140:00 O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0141:00 O2 Sensor Heater Circuit (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P014A:00 O2 Sensor Delayed Response - Rich to Lean (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0150:00 O2 Sensor Circuit (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0151:00 O2 Sensor Circuit Low Voltage (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0152:00 O2 Sensor Circuit High Voltage (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0153:00 O2 Sensor Circuit Slow Response (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0154:00 O2 Sensor Circuit No Activity Detected (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0155:00 O2 Sensor Heater Circuit (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P0157:00 O2 Sensor Circuit Low Voltage (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0158:00 O2 Sensor Circuit High Voltage (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0159:00 O2 Sensor Circuit Slow Response (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P0161:00 O2 Sensor Heater Circuit (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P016A:00 Excessive Time to Enter Closed Loop Air/Fuel Ratio Control: No Sub Type Information GO to Pinpoint Test DW
PCM P0171:00 System Too Lean Bank 1: No Sub Type Information GO to Pinpoint Test H
PCM P0172:00 System Too Rich Bank 1: No Sub Type Information GO to Pinpoint Test H
PCM P0174:00 System Too Lean Bank 2: No Sub Type Information GO to Pinpoint Test H
PCM P0175:00 System Too Rich Bank 2: No Sub Type Information GO to Pinpoint Test H
PCM P064D:00 O2 Sensor Signal Processor Internal Control Module Performance - Bank 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P064E:00 O2 Sensor Signal Processor Internal Control Module Performance - Bank 2: No Sub Type Information GO to Pinpoint Test DZ
PCM P1127:00 Exhaust Gas Temperature Out of Range, O2 Sensor Tests Not Complete: No Sub Type Information GO to Pinpoint Test DZ
PCM P1137:00 Lack of HO2S12 Switching - Sensor Indicates Lean: No Sub Type Information GO to Pinpoint Test H
PCM P1138:00 Lack of HO2S12 Switching - Sensor Indicates Rich: No Sub Type Information GO to Pinpoint Test H
PCM P1157:00 Lack of HO2S22 Switching - Sensor Indicates Lean: No Sub Type Information GO to Pinpoint Test H
PCM P1158:00 Lack of HO2S22 Switching - Sensor Indicates Rich: No Sub Type Information GO to Pinpoint Test H
PCM P1646:00 Linear Oxygen Sensor Control Chip (Bank 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P1647:00 Linear Oxygen Sensor Control Chip (Bank 2): No Sub Type Information GO to Pinpoint Test DZ
PCM P164A:00 O2 Sensor Positive Current Control Circuit Performance (Bank 1, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P164B:00 O2 Sensor Positive Current Control Circuit Performance (Bank 2, Sensor 1): No Sub Type Information GO to Pinpoint Test DZ
PCM P2096:00 Fuel Trim System Lean After Catalytic Converter, Bank 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2097:00 Fuel Trim System Rich After Catalytic Converter, Bank 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2098:00 Fuel Trim System Lean After Catalytic Converter, Bank 2: No Sub Type Information GO to Pinpoint Test DZ
PCM P2099:00 Fuel Trim System Rich After Catalytic Converter, Bank 2: No Sub Type Information GO to Pinpoint Test DZ
PCM P2195:00 O2 Sensor Stuck/Biased Lean – Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test H
PCM P2196:00 O2 Sensor Stuck/Biased Rich – Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test H
PCM P2197:00 O2 Sensor Stuck/Biased Lean – Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test H
PCM P2198:00 O2 Sensor Stuck/Biased Rich – Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test H
PCM P219A:00 Bank 1 Air-Fuel Ratio Imbalance: No Sub Type Information GO to Pinpoint Test H
PCM P219B:00 Bank 2 Air-Fuel Ratio Imbalance: No Sub Type Information GO to Pinpoint Test H
PCM P219C:00 Air-Fuel Ratio Imbalance Cylinder 1: No Sub Type Information GO to Pinpoint Test H
PCM P219D:00 Air-Fuel Ratio Imbalance Cylinder 2: No Sub Type Information GO to Pinpoint Test H
PCM P219E:00 Air-Fuel Ratio Imbalance Cylinder 3: No Sub Type Information GO to Pinpoint Test H
PCM P219F:00 Air-Fuel Ratio Imbalance Cylinder 4: No Sub Type Information GO to Pinpoint Test H
PCM P21A0:00 Air-Fuel Ratio Imbalance Cylinder 5: No Sub Type Information GO to Pinpoint Test H
PCM P21A1:00 Air-Fuel Ratio Imbalance Cylinder 6: No Sub Type Information GO to Pinpoint Test H
PCM P2237:00 O2 Sensor Positive Current Control Circuit / Open – Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2240:00 O2 Sensor Positive Current Control Circuit / Open – Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2243:00 O2 Sensor Reference Voltage Circuit / Open – Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2247:00 O2 Sensor Reference Voltage Circuit / Open – Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2251:00 O2 Sensor Negative Current Control Circuit / Open – Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2254:00 O2 Sensor Negative Current Control Circuit / Open – Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2270:00 O2 Sensor Stuck Lean – Bank 1, Sensor 2: No Sub Type Information GO to Pinpoint Test DW
PCM P2270:00 O2 Sensor Stuck Lean – Bank 1, Sensor 2: No Sub Type Information GO to Pinpoint Test H
PCM P2271:00 O2 Sensor Stuck Rich – Bank 1, Sensor 2: No Sub Type Information GO to Pinpoint Test DW
PCM P2271:00 O2 Sensor Stuck Rich – Bank 1, Sensor 2: No Sub Type Information GO to Pinpoint Test H
PCM P2272:00 O2 Sensor Stuck Lean – Bank 2, Sensor 2: No Sub Type Information GO to Pinpoint Test DW
PCM P2272:00 O2 Sensor Stuck Lean – Bank 2, Sensor 2: No Sub Type Information GO to Pinpoint Test H
PCM P2273:00 O2 Sensor Stuck Rich – Bank 2, Sensor 2: No Sub Type Information GO to Pinpoint Test DW
PCM P2273:00 O2 Sensor Stuck Rich – Bank 2, Sensor 2: No Sub Type Information GO to Pinpoint Test H
PCM P2297:00 O2 Sensor Out of Range During Deceleration, Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DW
PCM P2626:00 O2 Sensor Positive Current Trim Circuit / Open Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2627:00 O2 Sensor Positive Current Trim Circuit Low, Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2628:00 O2 Sensor Positive Current Trim Circuit High, Bank 1, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2629:00 O2 Sensor Positive Current Trim Circuit / Open Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2630:00 O2 Sensor Positive Current Trim Circuit Low, Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2631:00 O2 Sensor Positive Current Trim Circuit High, Bank 2, Sensor 1: No Sub Type Information GO to Pinpoint Test DZ
PCM P2A01:00 O2 Circuit Range/Performance (Bank 1, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P2A04:00 O2 Circuit Range/Performance (Bank 2, Sensor 2): No Sub Type Information GO to Pinpoint Test DW
PCM P2BEC:00 Fuel Injection Control System "A" Too Lean, Bank 1: No Sub Type Information GO to Pinpoint Test H
PCM P2BED:00 Fuel Injection Control System "A" Too Rich, Bank 1: No Sub Type Information GO to Pinpoint Test H
PCM P2BEE:00 Fuel Injection Control System "A" Too Lean, Bank 2: No Sub Type Information GO to Pinpoint Test H
PCM P2BEF:00 Fuel Injection Control System "A" Too Rich, Bank 2: No Sub Type Information GO to Pinpoint Test H
PCM P2BF0:00 Fuel Injection Control System "B" Too Lean, Bank 1: No Sub Type Information GO to Pinpoint Test H
PCM P2BF1:00 Fuel Injection Control System "B" Too Rich, Bank 1: No Sub Type Information GO to Pinpoint Test H
PCM P2BF2:00 Fuel Injection Control System "B" Too Lean, Bank 2: No Sub Type Information GO to Pinpoint Test H
PCM P2BF3:00 Fuel Injection Control System "B" Too Rich, Bank 2: No Sub Type Information GO to Pinpoint Test H

Symptom Chart

Symptom Possible Sources Action
  • Engine Runs Rough.
  • Refer to Pinpoint Test.
  • GO to Pinpoint Test DZ
  • Engine Has Backfire.
  • Refer to Pinpoint Test.
  • GO to Pinpoint Test H

Pinpoint Tests


PINPOINT TEST DW: HEATED OXYGEN SENSOR (HO2S)
Introduction

Normal Operation and Fault Symptoms

Refer to DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
PCM P0030:00 HO2S Sensor Heater Control Circuit (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the on and off duty cycle of the heater to maintain the calibrated temperature.
PCM P0036:00 HO2S Sensor Heater Control Circuit (Bank 1, Sensor 2): No Sub Type Information Sets when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the on and off duty cycle of the HO2S heater, Bank 1, Sensor 2 to maintain the calibrated temperature.
PCM P0037:00 HO2S Sensor Heater Control Circuit Low (Bank 1, Sensor 2): No Sub Type Information Sets when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the on and off duty cycle of the HO2S heater, Bank 1, Sensor 2 to maintain the calibrated temperature.
PCM P0038:00 HO2S Sensor Heater Control Circuit High (Bank 1, Sensor 2): No Sub Type Information Sets when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the on and off duty cycle of the HO2S heater, Bank 1, Sensor 2 to maintain the calibrated temperature.
PCM P0041:00 Oxygen Sensor Signals Crossed: Bank 1 Sensor 2 / Bank 2 Sensor 2: No Sub Type Information Sets when the PCM detects that the HO2S does not respond as expected. The HO2S monitor determines whether the HO2S signal response to fuel offset corresponds to the correct engine bank. Connect the HO2S connector to the correct bank.
PCM P0053:00 HO2S Sensor Heater Resistance (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects that the heater current demand is too low or too high in the HTR11 circuit.
PCM P0054:00 HO2S Sensor Heater Resistance (Bank 1, Sensor 2): No Sub Type Information Sets when the PCM detects that the heater current demand is too low or too high in the HTR12 circuit.
PCM P0056:00 HO2S Sensor Heater Control Circuit (Bank 2, Sensor 2): No Sub Type Information Set when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the on and off cycling of the HO2S Heater Bank 1 Sensor 2 heater to maintain the calibrated temperature.
PCM P0060:00 HO2S Sensor Heater Resistance (Bank 2, Sensor 2): No Sub Type Information Set when the PCM detects that the heater current requirements are too low or too high on the HTR22 circuit.
PCM P00D2:00 HO2S Sensor Heater Control Circuit Range/Performance (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects that the internal resistance of the Heated Oxygen Sensor Bank 1 Sensor 2 heater element exceeds the calibrated threshold.
PCM P0130:00 O2 Sensor Circuit (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0131:00 O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas. Engine stall condition or a rich air-fuel ratio condition may also set this DTC. Before diagnosing this DTC, check for any engine stall or rich air-fuel ratio conditions.
PCM P0132:00 O2 Sensor Circuit High Voltage (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects a voltage high condition in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0133:00 O2 Sensor Circuit Slow Response (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects that the oxygen sensor signal does not reach the expected amplitude within the specified response time. The PCM monitors the oxygen sensor response time by commanding a calibrated fuel control routine. This procedure sets the air-fuel ratio to a calibrated limit to obtain a predictable oxygen sensor signal amplitude.
PCM P0134:00 O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 1): No Sub Type Information Set when the PCM does not detect movement in the sensor signal while the air-fuel ratio oscillates. If the sensor signal value does not change from the default value, the PCM commands an oscillating air-fuel ratio in an attempt to detect some change in the signal value.
PCM P0135:00 O2 Sensor Heater Circuit (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects an open circuit, short circuit, or heater current draw exceeding the calibrated limit.
PCM P0136:00 O2 Sensor Circuit (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0137:00 O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0138:00 O2 Sensor Circuit High Voltage (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects a voltage high condition in the HO2S12 circuit.
PCM P0139:00 O2 Sensor Circuit Slow Response (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects that it is at or has exceeded the allowable time limit for fuel trim modification without detecting an acceptable voltage change rate. The HO2S monitor monitors the voltage change rate during the rise and fall of the HO2S Bank 1 Sensor 2 (HO2S12) signal. When the voltage change rate is less than the calibrated value, the PCM begins to modify fuel delivery correction in an attempt to increase the HO2S voltage switching rate.
PCM P013A:00 O2 Sensor Slow Response - Rich to Lean (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects that the measured response rate is below the threshold value. This monitor is very sensitive to exhaust leaks near the rear HO2S. The Heated Oxygen Sensor Monitor measures the rear HO2S response rate for the transition from rich to lean. This monitor is very sensitive to exhaust leaks near the rear HO2S. Check the exhaust system for leaks.
PCM P013B:00 O2 Sensor Slow Response - Lean to Rich (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects that the measured rate is slower than the threshold value. During deceleration fuel shut-off, the PCM monitors how quickly the HO2S Bank 1 Sensor 2 switches from lean to rich. The measured lean-to-rich switching rate is compared with the calibrated fault threshold value. Check the exhaust system for leaks.
PCM P013C:00 O2 Sensor Slow Response - Rich to Lean (Bank 2, Sensor 2): No Sub Type Information Set when the PCM detects that the measured response rate is below the threshold value. This monitor is very sensitive to exhaust leaks near the rear HO2S. The Heated Oxygen Sensor Monitor measures the rear HO2S response rate for the transition from rich to lean. This monitor is very sensitive to exhaust leaks near the rear HO2S. Check the exhaust system for leaks.
PCM P013E:00 O2 Sensor Delayed Response - Rich to Lean (Bank 1, Sensor 2): No Sub Type Information Set when the PCM, after three consecutive intrusive attempts, cannot cause the signal to exceed the calibrated rich value. Also, if the signal voltage remains above the lean value after a calibrated amount of time with the fuel injectors off, the counter increments. This DTC also sets when, after three consecutive occurrences, the signal does not drop below the calibrated lean value. During deceleration fuel shut-off, the PCM monitors the HO2S Bank 1 Sensor 2 signal to determine whether the signal is stuck within the range. The PCM expects the signal to exceed the calibrated rich or lean value within a calibrated amount of time. If the signal voltage remains below the rich value after a number of occurrences, the PCM intrusively monitors fuel enrichment for increasing periods of time in an attempt to drive the signal above the calibrated rich value. Check the exhaust system for leaks. Check for an intermittent HO2S12 signal or HO2S22 signal.
PCM P0140:00 O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 2): No Sub Type Information Set when the PCM cannot detect movement in the sensor signal while the air-fuel ratio oscillates. If the sensor signal value does not change from the default value, the PCM commands an oscillating air-fuel ratio in an attempt to detect some movement in the signal value. HO2S12 PID switching from 0.2 V to 0.9 V at 0.45 V indicates normal HO2S switching.
PCM P0141:00 O2 Sensor Heater Circuit (Bank 1, Sensor 2): No Sub Type Information Set when the PCM detects an open circuit or short circuit, or the HO2S Bank 1 Sensor 2 heater current draw exceeds the calibrated limit.
PCM P014A:00 O2 Sensor Delayed Response - Rich to Lean (Bank 2, Sensor 2): No Sub Type Information Sets when the PCM, after three consecutive intrusive attempts, cannot force the signal above the calibrated rich value. Also, if the signal voltage remains above the lean value after a calibrated amount of time with the fuel injectors off, the counter increments. This DTC also sets when, after three consecutive occurrences, the signal is not less than the calibrated lean value. During Deceleration Fuel Shut-Off (DFSO), the PCM monitors HO2S Bank 2 Sensor 2 signal to determine whether the signal is stuck in range. The PCM expects the signal to exceed the calibrated rich or lean value within a calibrated amount of time. If the signal voltage remains below the rich value after a number of occurrences, the PCM intrusively controls fuel system enrichment for increasing periods of time in an attempt to force the signal above the calibrated rich value. Check for exhaust leaks. Check for an intermittent HO2S12 or HO2S22 signal.
PCM P0157:00 O2 Sensor Circuit Low Voltage (Bank 2, Sensor 2): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0158:00 O2 Sensor Circuit High Voltage (Bank 2, Sensor 2): No Sub Type Information Sets when the PCM detects a high voltage condition in the HO2S Bank 2 Sensor 2 circuit.
PCM P0159:00 O2 Sensor Circuit Slow Response (Bank 2, Sensor 2): No Sub Type Information Sets when the PCM detects that it is at or has exceeded the allowable time limit for fuel trim modification without detecting an acceptable voltage switching rate. The HO2S monitor monitors the voltage switching rate during the rise and fall of the HO2S Bank 2 Sensor 2 signal. When the voltage switching rate is less than the calibrated value, the PCM begins modifying fuel trim in an attempt to increase the HO2S voltage switching rate.
PCM P0161:00 O2 Sensor Heater Circuit (Bank 2, Sensor 2): No Sub Type Information Sets when the PCM detects an open or short circuit in the HO2S heater circuit, Bank 2, Sensor 2.
PCM P016A:00 Excessive Time to Enter Closed Loop Air/Fuel Ratio Control: No Sub Type Information Sets when the PCM detects that it is at or has exceeded the allowable time limit for fuel trim modification without detecting an acceptable voltage switching rate. The HO2S monitor monitors the voltage switching rate during the rise and fall of the HO2S signal. When the voltage switching rate is less than the calibrated value, the PCM begins modifying fuel trim in an attempt to increase the HO2S voltage switching rate.
PCM P2270:00 O2 Sensor Stuck Lean – Bank 1, Sensor 2: No Sub Type Information Sets when the PCM detects that the HO2S Bank 1 Sensor 2 signal is below the calibrated rich value during the current key cycle and, after three consecutive intrusive events, the signal cannot be forced above the calibrated rich value. Check for exhaust leaks. Check for an intermittent HO2S12 signal.
PCM P2271:00 O2 Sensor Stuck Rich – Bank 1, Sensor 2: No Sub Type Information Sets when the PCM detects that the HO2S Bank 1 Sensor 2 signal is above the calibrated lean value during the current key cycle and, after three consecutive intrusive events, the signal cannot be forced below the calibrated lean value. Check for exhaust leaks. Check for an intermittent HO2S12 signal.
PCM P2272:00 O2 Sensor Stuck Lean – Bank 2, Sensor 2: No Sub Type Information Sets when the PCM detects that the HO2S Bank 2 Sensor 2 signal is below the calibrated rich value during the current key cycle and, after three consecutive intrusive events, the signal cannot be forced above the calibrated rich value. Check for exhaust leaks. Check for an intermittent HO2S22 signal.
PCM P2273:00 O2 Sensor Stuck Rich – Bank 2, Sensor 2: No Sub Type Information This DTC sets when the HO2S Bank 2 Sensor 2 signal is above the calibrated lean value during the current key cycle and, after three consecutive intrusive events, the signal cannot be forced below the calibrated lean value. Check for exhaust leaks. Check for an intermittent HO2S22 signal.
PCM P2297:00 O2 Sensor Out of Range During Deceleration, Bank 1, Sensor 1: No Sub Type Information Sets when the PCM detects that the measured value for HO2S Bank 1 Sensor 1 is slower than the measured value for HO2S Bank 1 Sensor 2. During Deceleration Fuel Shut-Off, the PCM monitors how quickly the rear oxygen sensor switches from rich to lean. The measured rich-to-lean switch rate is compared with a calibrated threshold value. The threshold value accounts for the oxygen level in the catalyst, which affects how quickly the rich-to-lean switch occurs. Check for exhaust leaks.
PCM P2A01:00 O2 Circuit Range/Performance (Bank 1, Sensor 2): No Sub Type Information Sets when the PCM detects that the HO2S Bank 1 Sensor 2 voltage is below the low range limit for a calibrated period of time.
PCM P2A04:00 O2 Circuit Range/Performance (Bank 2, Sensor 2): No Sub Type Information Sets when the PCM detects that the HO2S Bank 2 Sensor 2 voltage is below the low range limit for a calibrated period of time.

Possible Sources

  • Aftermarket accessories or performance modifications
  • Exhaust gas leak
  • High exhaust temperature
  • Contaminated Fuel
  • HO2S circuit problem
  • Mass Air Flow (MAF) sensor (if equipped)
  • Oxygen sensor (9G444)
  • PCM (12A650)
PINPOINT TEST DZ: UNIVERSAL HEATED OXYGEN SENSOR (HO2S)
Introduction

Normal Operation and Fault Symptoms

Refer to DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
PCM P0030:00 HO2S Sensor Heater Control Circuit (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the on and off duty cycle of the heater to maintain the calibrated temperature.
PCM P0040:00 Oxygen Sensor Signals Crossed Bank 1 Sensor 1 / Bank 1 Sensor 2: No Sub Type Information Sets when the PCM does not detect a response from the tested HO2S. The HO2S monitor determines whether the HO2S signal response to fuel offset matches the correct engine bank. Connect the HO2S connector to the correct bank.
PCM P0050:00 HO2S Sensor Heater Control Circuit (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects that the sensor does not heat up to the required temperature within a calibrated amount of time. This DTC also sets when the PCM cannot maintain the required temperature after the sensor is warm. The PCM controls the HO2S Bank 2 Sensor 1 heater ON and OFF duty cycle to maintain the calibrated temperature.
PCM P0053:00 HO2S Sensor Heater Resistance (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects that the heater current in the UO2SHTR11 circuit is too low or too high.
PCM P0059:00 HO2S Sensor Heater Resistance (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects that the heater current demand is too low or too high in the UO2SHTR21 circuit.
PCM P0130:00 O2 Sensor Circuit (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0131:00 O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects a problem with one of the circuits used to determine the oxygen content in the exhaust gas. This DTC may also be set by an engine stall condition or an excessively rich air/fuel ratio. Diagnose any engine stall or rich air/fuel ratio concerns before diagnosing this DTC.
PCM P0132:00 O2 Sensor Circuit High Voltage (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects a high voltage condition in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0133:00 O2 Sensor Circuit Slow Response (Bank 1, Sensor 1): No Sub Type Information Set when the PCM detects that the oxygen sensor signal does not reach the expected amplitude within the specified response time. The PCM monitors the oxygen sensor response time by commanding a calibrated fuel control routine. This procedure sets the air-fuel ratio to a calibrated limit to obtain a predictable oxygen sensor signal amplitude.
PCM P0134:00 O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM cannot detect any movement in the sensor signal while the air/fuel ratio is oscillating. If the sensor signal value does not change from the default value, the PCM commands the air/fuel ratio to oscillate, attempting to detect some movement in the signal value.
PCM P0135:00 O2 Sensor Heater Circuit (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects an open circuit or short circuit, or the heater current draw exceeds the calibrated limit.
PCM P0150:00 O2 Sensor Circuit (Bank 2, Sensor 1): No Sub Type Information Set when the PCM detects a fault in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0151:00 O2 Sensor Circuit Low Voltage (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects a problem with one of the circuits used to determine the oxygen content in the exhaust gas. This DTC may also be set by an engine stall condition or an excessively rich air/fuel ratio. Diagnose any engine stall or rich air/fuel ratio concerns before diagnosing this DTC.
PCM P0152:00 O2 Sensor Circuit High Voltage (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects a high voltage condition in one of the circuits used to determine the oxygen content in the exhaust gas.
PCM P0153:00 O2 Sensor Circuit Slow Response (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects that the oxygen sensor signal does not reach the expected amplitude within the specified response time. The PCM monitors the Universal HO2S Bank 2 Sensor 1 response time while commanding a calibrated fuel control routine. This procedure sets the air/fuel ratio to a calibrated limit to produce a predictable oxygen sensor signal amplitude.
PCM P0154:00 O2 Sensor Circuit No Activity Detected (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM does not detect any movement in the sensor signal while the air/fuel ratio is oscillating. If the sensor signal value does not change from the default value, the PCM commands the air/fuel ratio to oscillate, attempting to detect some movement in the signal value.
PCM P0155:00 O2 Sensor Heater Circuit (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects an open circuit, a short circuit, or the Universal Heated Oxygen Sensor (HO2S) Bank 2 Sensor 1 heater current draw exceeds the calibrated limit.
PCM P064D:00 O2 Sensor Signal Processor Internal Control Module Performance - Bank 1: No Sub Type Information Sets when the PCM detects an internal circuit or communication problem. The PCM monitors the dedicated integrated circuit that controls and monitors the Universal Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1. Check for and diagnose any other Diagnostic Trouble Codes (DTCs) first. Check for intermittent faults in the Universal HO2S wiring. Inspect the Universal HO2S wiring between the PCM and the sensor for damage. Check for aftermarket products. Reprogram or update the calibration. Clear the DTCs and repeat the self-test.
PCM P064E:00 O2 Sensor Signal Processor Internal Control Module Performance - Bank 2: No Sub Type Information Sets when the PCM detects an internal circuit or communication problem. The PCM monitors the dedicated integrated circuit that controls and monitors the Universal HO2S Bank 2 Sensor 1. Check for and diagnose any other Diagnostic Trouble Codes (DTCs) first. Check for intermittent faults in the Universal HO2S wiring. Inspect the Universal HO2S wiring between the PCM and the sensor for damage. Check for aftermarket products. Reprogram or update the calibration. Clear the DTCs and repeat the self-test.
PCM P1127:00 Exhaust Gas Temperature Out of Range, O2 Sensor Tests Not Complete: No Sub Type Information Sets when the PCM detects that the estimated exhaust gas temperature is below the minimum calibrated value. DTC P1127 is present if the exhaust is not hot. The HO2S uses an exhaust gas temperature model to determine when to turn on the Universal HO2S heaters. Monitor the Universal HO2S heater PIDs to determine the ON or OFF status. DTC P1127 is present if the exhaust is not hot.
PCM P1646:00 Linear Oxygen Sensor Control Chip (Bank 1): No Sub Type Information Sets when the PCM detects an internal circuit or communication problem. The PCM monitors the dedicated integrated circuit that controls and monitors the Universal HO2S Bank 1 Sensor 1. Check for and diagnose any other Diagnostic Trouble Codes (DTCs) first. Check for intermittent faults in the Universal HO2S wiring. Inspect the Universal HO2S wiring between the PCM and the sensor for damage. Check for aftermarket products. Reprogram or update the calibration. Clear the DTCs and repeat the self-test.
PCM P1647:00 Linear Oxygen Sensor Control Chip (Bank 2): No Sub Type Information Sets when the PCM detects an internal circuit or communication problem. The PCM monitors the dedicated integrated circuit that controls and monitors the Universal HO2S Bank 2 Sensor 1. Check for and diagnose any other Diagnostic Trouble Codes (DTCs) first. Check for intermittent faults in the Universal HO2S wiring. Inspect the Universal HO2S wiring between the PCM and the sensor for damage. Check for aftermarket products. Reprogram or update the calibration. Clear the DTCs and repeat the self-test.
PCM P164A:00 O2 Sensor Positive Current Control Circuit Performance (Bank 1, Sensor 1): No Sub Type Information Sets when the PCM detects an inconsistent or incorrect resistor measurement. The resistor is installed in the Universal HO2S Bank 1 Sensor 1 connector for part-to-part variation. The PCM determines the value of this resistor by taking several resistor measurements during each ignition cycle. The PCM uses this value to compensate for differences in the pump current signal.
PCM P164B:00 O2 Sensor Positive Current Control Circuit Performance (Bank 2, Sensor 1): No Sub Type Information Sets when the PCM detects an inconsistent or incorrect resistor measurement. The resistor is installed in the Universal HO2S Bank 2 Sensor 1 connector for part-to-part variation. The PCM determines the value of this resistor by taking several resistor measurements during each ignition cycle. The PCM uses this value to compensate for differences in the pump current signal.
PCM P2096:00 Fuel Trim System Lean After Catalytic Converter, Bank 1: No Sub Type Information Set when the PCM detects that the correction value is greater than the calibrated limit. The PCM monitors the correction value from the HO2S sensor, Bank 1, Sensor 2 as part of the front oxygen sensor control procedure.
PCM P2097:00 Fuel Trim System Rich After Catalytic Converter, Bank 1: No Sub Type Information Set when the PCM detects that the correction value is greater than the calibrated limit. The PCM monitors the correction value from the HO2S sensor, Bank 1, Sensor 2 as part of the front oxygen sensor control procedure.
PCM P2098:00 Fuel Trim System Lean After Catalytic Converter, Bank 2: No Sub Type Information Set when the PCM detects that the correction value is greater than the calibrated limit. The PCM monitors the correction value from the HO2S sensor, Bank 2, Sensor 2 as part of the front oxygen sensor control procedure.
PCM P2099:00 Fuel Trim System Rich After Catalytic Converter, Bank 2: No Sub Type Information Set when the PCM detects that the correction value is greater than the calibrated limit. The PCM monitors the correction value from the HO2S sensor, Bank 2, Sensor 2 as part of the front oxygen sensor control procedure.
PCM P2237:00 O2 Sensor Positive Current Control Circuit / Open – Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2240:00 O2 Sensor Positive Current Control Circuit / Open – Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2243:00 O2 Sensor Reference Voltage Circuit / Open – Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2247:00 O2 Sensor Reference Voltage Circuit / Open – Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2251:00 O2 Sensor Negative Current Control Circuit / Open – Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2254:00 O2 Sensor Negative Current Control Circuit / Open – Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2626:00 O2 Sensor Positive Current Trim Circuit / Open Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects that the actual oxygen sensor voltage exceeds the maximum expected voltage threshold for a specified period of time. During deceleration fuel shut-off, the PCM monitors the UO2SPCT11 circuit integrity by comparing the actual oxygen sensor voltage signal to the expected oxygen sensor voltage signal.
PCM P2627:00 O2 Sensor Positive Current Trim Circuit Low, Bank 1, Sensor 1: No Sub Type Information Set when the PCM determines that the HO2S wide-range sensor resistance value is too high. A resistor is installed in the HO2S wide-range connector to compensate for part-to-part differences. The PCM determines the value of this resistor by taking multiple resistor measurements at each ignition on event. The PCM uses this value to compensate for variance in the pump current signal.
PCM P2628:00 O2 Sensor Positive Current Trim Circuit High, Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.
PCM P2629:00 O2 Sensor Positive Current Trim Circuit / Open Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects that the actual oxygen sensor voltage exceeds the maximum expected voltage threshold for a specified period of time. During deceleration fuel shut-off, the PCM monitors the UO2SPCT21 circuit integrity by comparing the actual oxygen sensor voltage signal to the expected oxygen sensor voltage signal.
PCM P2630:00 O2 Sensor Positive Current Trim Circuit Low, Bank 2, Sensor 1: No Sub Type Information Set when the PCM determines that the HO2S wide-range sensor resistance value is too high. A resistor is installed in the HO2S wide-range connector to compensate for part-to-part differences. The PCM determines the value of this resistor by taking multiple resistor measurements at each ignition on event. The PCM uses this value to compensate for variance in the pump current signal.
PCM P2631:00 O2 Sensor Positive Current Trim Circuit High, Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects a fault in the circuit used to determine the oxygen content in the exhaust gas.

Possible Sources

  • HO2S circuit problem
  • Exhaust gas leak
  • Intake Air Leak
  • Engine has not run long enough before performing the KOER self-test.
  • Mass Air Flow (MAF) sensor (if equipped)
  • Oxygen Sensor (9Y460)
  • PCM (12A650)
PINPOINT TEST H: FUEL CONTROL
Introduction

Normal Operation and Fault Symptoms

Refer to DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
PCM P0171:00 System Too Lean Bank 1: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the rich calibrated limit. Refer to Fuel Trim for additional information. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Review the freeze frame data to determine the operating conditions when the DTC was set. Monitor the LONGFT1 and LONGFT2 PIDs.
PCM P0172:00 System Too Rich Bank 1: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the lean calibrated limit. Refer to Fuel Trim for additional information. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Review the freeze frame data to determine the operating conditions when the DTC was set. Monitor the LONGFT1 and LONGFT2 PIDs.
PCM P0174:00 System Too Lean Bank 2: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the rich calibrated limit. Refer to Fuel Trim for additional information. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Review the freeze frame data to determine the operating conditions when the DTC was set. Monitor the LONGFT1 and LONGFT2 PIDs.
PCM P0175:00 System Too Rich Bank 2: No Sub Type Information The adaptive fuel strategy continuously monitors the fuel delivery hardware. This DTC is set when the adaptive fuel tables reach the lean calibrated limit. Refer to Fuel Trim for additional information. Review the freeze frame data to determine the operating conditions when the DTC was set. Monitor the LONGFT1 and LONGFT2 PIDs.
PCM P1137:00 Lack of HO2S12 Switching - Sensor Indicates Lean: No Sub Type Information Set when the PCM detects no output signal from the HO2S12 circuit within a calibrated amount of time. The HO2S, Bank 1, Sensor 2 is forced rich and lean and monitored by the PCM.
PCM P1138:00 Lack of HO2S12 Switching - Sensor Indicates Rich: No Sub Type Information Set when the PCM detects no output signal from the HO2S12 circuit within a calibrated amount of time. The HO2S, Bank 1, Sensor 2 is forced rich and lean and monitored by the PCM.
PCM P1157:00 Lack of HO2S22 Switching - Sensor Indicates Lean: No Sub Type Information Set when the PCM detects no output signal from the HO2S22 sensor within a calibrated amount of time. The HO2S, Bank 2, Sensor 2 is forced rich and lean and monitored by the PCM.
PCM P1158:00 Lack of HO2S22 Switching - Sensor Indicates Rich: No Sub Type Information Set when the PCM detects no output signal from the HO2S22 sensor within a calibrated amount of time. The HO2S, Bank 2, Sensor 2 is forced rich and lean and monitored by the PCM.
PCM P2195:00 O2 Sensor Stuck/Biased Lean – Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects that the fuel control system does not switch within a calibrated amount of time. The HO2S, Bank 1, Sensor 1 indicates lean at the end of the test and attempts to correct the excessive lean condition.
PCM P2196:00 O2 Sensor Stuck/Biased Rich – Bank 1, Sensor 1: No Sub Type Information Set when the PCM detects that the fuel control system does not switch within a calibrated amount of time. The HO2S, Bank 1, Sensor 1 indicates rich at the end of the test and attempts to correct the excessive rich condition.
PCM P2197:00 O2 Sensor Stuck/Biased Lean – Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects that the fuel control system does not switch within a calibrated amount of time. The HO2S, Bank 2, Sensor 1 indicates lean at the end of the test and attempts to correct the excessive lean condition.
PCM P2198:00 O2 Sensor Stuck/Biased Rich – Bank 2, Sensor 1: No Sub Type Information Set when the PCM detects that the fuel control system does not switch within a calibrated amount of time. The HO2S, Bank 2, Sensor 1 indicates rich at the end of the test and attempts to correct the excessive rich condition.
PCM P219A:00 Bank 1 Air-Fuel Ratio Imbalance: No Sub Type Information Set when the PCM detects that the air-fuel ratio difference per cylinder is greater than the calculated amount. The Air-Fuel Ratio Imbalance Monitor is designed to detect large differences in the air-fuel ratio between the cylinders of an engine bank.
PCM P219B:00 Bank 2 Air-Fuel Ratio Imbalance: No Sub Type Information Set when the PCM detects that the air-fuel ratio difference per cylinder is greater than the calculated amount. The Air-Fuel Ratio Imbalance Monitor is designed to detect large differences in the air-fuel ratio between the cylinders of an engine bank.
PCM P219C:00 Air-Fuel Ratio Imbalance Cylinder 1: No Sub Type Information Set when the PCM detects that the minimum air-fuel ratio difference in Cylinder 1 is greater than the calculated amount. The Air-Fuel Ratio Imbalance Torque Monitor is designed to detect minimal differences in the air-fuel ratio between the cylinders. This DTC may be caused by other systems related to Cylinder 1. Diagnose any other DTCs related to Cylinder 1 first. The CKP sensor signal is very sensitive to electrical noise. Inspect the Crankshaft Position Sensor harness routing.
PCM P219D:00 Air-Fuel Ratio Imbalance Cylinder 2: No Sub Type Information Set when the PCM detects a fuel-air ratio imbalance between cylinder 2 and the other cylinders that exceeds the calculated limit. The Air-Fuel Ratio Imbalance Monitor is designed to detect minimum differences in the air-fuel ratio between cylinders. This DTC may be caused by other systems related to cylinder 2. Diagnose any other DTCs related to cylinder 1 first. The CKP sensor signal is very sensitive to electrical interference. Inspect the CKP sensor harness wiring shield.
PCM P219E:00 Air-Fuel Ratio Imbalance Cylinder 3: No Sub Type Information Set when the PCM detects a fuel-air ratio imbalance between cylinder 3 and the other cylinders that exceeds the calculated limit. The Air-Fuel Ratio Imbalance Monitor is designed to detect minimum differences in the air-fuel ratio between cylinders. This DTC may be caused by other systems related to cylinder 3. Diagnose any other DTCs related to cylinder 1 first. The CKP sensor signal is very sensitive to electrical interference. Inspect the CKP sensor harness wiring shield.
PCM P219F:00 Air-Fuel Ratio Imbalance Cylinder 4: No Sub Type Information Set when the PCM detects a fuel-air ratio imbalance between cylinder 4 and the other cylinders that exceeds the calculated limit. The Air-Fuel Ratio Imbalance Monitor is designed to detect minimum differences in the air-fuel ratio between cylinders. This DTC may be caused by other systems related to cylinder 4. Diagnose any other DTCs related to cylinder 1 first. The CKP sensor signal is very sensitive to electrical interference. Inspect the CKP sensor harness wiring shield.
PCM P21A0:00 Air-Fuel Ratio Imbalance Cylinder 5: No Sub Type Information Set when the PCM detects a fuel-air ratio imbalance between cylinder 5 and the other cylinders that exceeds the calculated limit. The Air-Fuel Ratio Imbalance Monitor is designed to detect minimum differences in the air-fuel ratio between cylinders. This DTC may be caused by other systems related to cylinder 5. Diagnose any other DTCs related to cylinder 1 first. The CKP sensor signal is very sensitive to electrical interference. Inspect the CKP sensor harness wiring shield.
PCM P21A1:00 Air-Fuel Ratio Imbalance Cylinder 6: No Sub Type Information Set when the PCM detects a fuel-air ratio imbalance between cylinder 6 and the other cylinders that exceeds the calculated limit. The Air-Fuel Ratio Imbalance Monitor is designed to detect minimum differences in the air-fuel ratio between cylinders. This DTC may be caused by other systems related to cylinder 6. Diagnose any other DTCs related to cylinder 1 first. The CKP sensor signal is very sensitive to electrical interference. Inspect the CKP sensor harness wiring shield.
PCM P2270:00 O2 Sensor Stuck Lean – Bank 1, Sensor 2: No Sub Type Information Set when the PCM does not detect a HO2S12 output signal within a calibrated amount of time. The HO2S Bank 1 Sensor 2 is forced rich and lean and monitored by the PCM. Check for exhaust system leaks. Check for an intermittent HO2S12 signal.
PCM P2271:00 O2 Sensor Stuck Rich – Bank 1, Sensor 2: No Sub Type Information Set when the PCM does not detect an HO2S output signal within a calibrated amount of time. The HO2S Bank 1 Sensor 2 is forced rich and lean and monitored by the PCM. Check for exhaust system leaks. Check for an intermittent HO2S12 signal.
PCM P2272:00 O2 Sensor Stuck Lean – Bank 2, Sensor 2: No Sub Type Information Set when the PCM does not detect a HO2S22 output signal within a calibrated amount of time. The HO2S Bank 2 Sensor 2 is forced rich and lean and monitored by the PCM. Check for exhaust system leaks. Check for an intermittent HO2S22 signal.
PCM P2273:00 O2 Sensor Stuck Rich – Bank 2, Sensor 2: No Sub Type Information Set when the PCM detects that it does not detect a HO2S22 output signal within a calibrated amount of time. The HO2S Bank 2 Sensor 2 is forced rich and lean and monitored by the PCM. Check for exhaust system leaks. Check for an intermittent HO2S22 signal.
PCM P2BEC:00 Fuel Injection Control System "A" Too Lean, Bank 1: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the rich calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BED:00 Fuel Injection Control System "A" Too Rich, Bank 1: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the lean calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BEE:00 Fuel Injection Control System "A" Too Lean, Bank 2: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the rich calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BEF:00 Fuel Injection Control System "A" Too Rich, Bank 2: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the lean calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BF0:00 Fuel Injection Control System "B" Too Lean, Bank 1: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the rich calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BF1:00 Fuel Injection Control System "B" Too Rich, Bank 1: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the lean calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BF2:00 Fuel Injection Control System "B" Too Lean, Bank 2: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the rich calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.
PCM P2BF3:00 Fuel Injection Control System "B" Too Rich, Bank 2: No Sub Type Information Set when the PCM detects that the adaptive fuel tables have reached the lean calibrated limit. The adaptive fuel strategy continuously monitors the fuel delivery hardware. Refer to Fuel Trim Correction for additional information. Review Freeze Frame data to determine the operating conditions when the DTC was set. Monitor PIDs LONGFT1 and LONGFT2.

Possible Sources

  • Aftermarket exhaust accessories or performance modifications
  • Ignition System Concern
  • Exhaust leak concern
  • Intake air leak concern
  • Vacuum leak concern
  • PCV system concern
  • Contaminated Fuel
  • Contaminated Oil
  • Fuel filter
  • Air filter
  • HO2S circuit problem
  • EVAP Purge Valve
  • Fuel line
  • Exhaust Gas Recirculation (EGR) Valve
  • EVAP Purge Valve
  • Fuel pump
  • Mass Air Flow (MAF) sensor (if equipped)
  • Oxygen sensor (9G444) or (9Y460)
  • Fuel injector (9F593)
  • PCM (12A650)

Test yourself

A quick Ford Escape quiz: every answer comes with an explanation and a link to the manual page.