Diagnosis and Testing - Exhaust Gas Recirculation (EGR) System

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).

Global Customer Symptom Codes (GCSC) Table

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).

Pinpoint Tests

PINPOINT TEST DS: EXHAUST GAS RECIRCULATION TEMPERATURE (EGRT) SENSOR

Introduction Normal Operation and Fault Symptoms Refer to DTC Fault Trigger Conditions. DTC Fault Trigger Conditions Trouble Code Description Fault Trigger Condition PCM P041B:00 EGR Temperature Sensor 'B' Circuit Range/Performance: no sub-type information Sets when the PCM detects EGRT Bank 1 Sensor 2 temperature less than or greater than a calibrated limit for a specified time. When EGRT Bank 1 Sensor 2 is less than or greater than the calibrated threshold, the incremental counter advances for this drive cycle. Diagnose any ECT or IAT2 sensor concerns before diagnosing this diagnostic trouble code. PCM P041C:00 EGR Temperature Sensor 'B' Circuit Low: no sub-type information Sets when the PCM detects EGRT Bank 1 Sensor 2 temperature greater than a calibrated limit for a specified time. When the EGRT Bank 1 Sensor 2 is less than or greater than the calibrated threshold, the incremental counter advances for this drive cycle. PCM P041D:00 EGR Temperature Sensor 'B' Circuit High: no sub-type information Sets when the PCM detects EGRT Bank 1 Sensor 2 temperature less than a calibrated limit for a specified time. When EGRT Bank 1 Sensor 2 is greater than the calibrated threshold, the incremental counter advances for this drive cycle. Possible Sources EGR Cooling System Concern EGRT Sensor Circuit Concern EGRT sensor

PINPOINT TEST DT: EXHAUST BACK PRESSURE SENSOR

Introduction Normal Operation and Fault Symptoms Refer to DTC Fault Trigger Conditions. DTC Fault Trigger Conditions Trouble Code Description Fault Trigger Condition PCM P0471:00 Exhaust Back Pressure Sensor 'A' Circuit Range/Performance: no sub-type information Sets when the PCM detects that the exhaust back pressure sensor signal is not within the calibrated value. The exhaust back pressure sensor reading must be greater than the BARO sensor reading by the calibrated threshold with the engine running. PCM P0472:00 Exhaust Back Pressure Sensor 'A' Circuit Low: no sub-type information Sets when the PCM detects that the exhaust back pressure sensor signal is less than the PCM self-test minimum. PCM P0473:00 Exhaust Back Pressure Sensor 'A' Circuit High: no sub-type information Sets when the PCM detects that the exhaust back pressure sensor signal is greater than the PCM self-test maximum. Possible Sources Exhaust Back Pressure Sensor Circuit Concern Exhaust Back Pressure Sensor (9J460) PCM (12A650)

PINPOINT TEST HE: EXHAUST GAS RECIRCULATION (EGR) SYSTEM

Introduction Normal Operation and Fault Symptoms Refer to DTC Fault Trigger Conditions. DTC Fault Trigger Conditions Trouble Code Description Fault Trigger Condition PCM P0401:00 Exhaust Gas Recirculation Flow Insufficient 'A': no sub-type information Sets when the PCM detects that the EGR feedback differential pressure sensor signal shows the EGR flow is less than the desired minimum. The EGR system is monitored during steady state driving conditions with EGR enabled. PCM P0402:00 Exhaust Gas Recirculation Flow Excessive 'A': no sub-type information Sets when the PCM detects that the idle signal is greater than the KOEO signal by a calibrated amount. The EGR system is monitored for unwanted EGR flow during idle. The EGR monitor looks at the EGR differential pressure feedback signal at idle and compares it with the stored signal measured during KOEO. A DPFEGR PID reading that is 0.5 volt higher at idle than during KOEO, or rough engine idle, may indicate a concern. PCM P044C:00 EGR Sensor 'C' Circuit Low: no sub-type information Sets when the PCM detects that the average voltage at the PCM drops below the minimum calibrated voltage. The EGR monitor checks the EGR differential pressure feedback sensor signal at the PCM for low voltage. PCM P044D:00 EGR Sensor 'C' Circuit High: no sub-type information Sets when the PCM detects that the average voltage at the PCM exceeds the maximum calibrated voltage. The EGR monitor checks the EGR differential pressure feedback sensor signal at the PCM for high voltage. PCM P139A:00 EGR Sensor 'C' Hoses Reversed: no sub-type information Sets when the PCM detects that the differential pressure reported by the sensor exceeds the maximum threshold or falls below the minimum threshold. At idle, the EGR monitor commands the EGR valve closed and checks the differential pressure at the EGR tube orifice, which should be zero to indicate the hoses are connected and not pinched. Look for signs of water or ice in the hose. Check the hose connection and routing. Check the EGR differential pressure feedback sensor for correct installation and operation. PCM P139B:00 EGR Sensor 'C' Upper Hose Disconnected or Plugged: no sub-type information Sets when the PCM detects that the differential pressure reported by the sensor exceeds the maximum threshold or falls below the minimum threshold. At idle, the EGR monitor commands the EGR valve closed and checks the differential pressure at the EGR tube orifice, which should be zero to indicate the hoses are connected and not pinched. Look for signs of water or ice in the hose. Check the hose connection and routing. Check the EGR differential pressure feedback sensor for correct installation and operation. PCM P139C:00 EGR Sensor 'C' Lower Hose Disconnected or Plugged: no sub-type information Sets when the PCM detects that the differential pressure reported by the sensor exceeds the maximum threshold or falls below the minimum threshold. At idle, the EGR monitor commands the EGR valve closed and checks the differential pressure at the EGR tube orifice, which should be zero to indicate the hoses are connected and not pinched. Look for signs of water or ice in the hose. Check the hose connection and routing. Check the EGR differential pressure feedback sensor for correct installation and operation. PCM P1408:00 EGR Flow Out of Self-Test Range: no sub-type information VEHICLES WITH DPFEGR Sets when the PCM detects that the measured EGR flow falls above or below the required calibration. This test is performed with the key on, engine off (KOEO) only, on-demand self-test. The EGR system is commanded on at a fixed engine speed. VEHICLES WITH ELECTRIC EGR Sets when the PCM detects that the measured EGR flow falls above or below the required calibration. This test is performed with the key on, engine off (KOEO) only, on-demand self-test. The EGR system is commanded on at a fixed engine speed. When using the scan tool output state control function and monitoring the MAP and EGRMDSD PIDs, command the EGR on. If EGR is commanded on at idle, the engine speed drops or the engine stalls. PCM P2457:00 EGR Cooler 'A' Efficiency Below Threshold: no sub-type information Sets when the PCM detects a difference between the expected exhaust gas temperature and the actual EGRT, bank 1, sensor 2 value that is greater than the calibrated amount. Possible Sources Cooling system problem EGR differential pressure feedback circuit problem EGR differential pressure feedback sensor hose Exhaust Gas Recirculation (EGR) Cooler Exhaust Gas Recirculation (EGR) Valve EGR differential pressure feedback sensor (9J460) Throttle tube assembly (9D477) PCM (12A650)

PINPOINT TEST KD: ELECTRIC EXHAUST GAS RECIRCULATION (EGR)

Introduction Normal Operation and Fault Symptoms Refer to DTC Fault Trigger Conditions. DTC Fault Trigger Conditions Trouble Code Description Fault Trigger Condition PCM P0400:00 EGR Flow A: no sub-type information Sets when the PCM detects a problem with the calculations indicating EGR flow is less than or greater than expected. The EGR system is monitored once per drive cycle under high and low load conditions. The following sensors provide input to the PCM for proper operation of the EGR system: EGT or EST CMP IAT MAF MAP TP Diagnose any diagnostic trouble code related to these sensors before addressing this diagnostic trouble code. PCM P0403:00 EGR Control Circuit 'A' Open: no sub-type information Sets when the PCM detects a problem with the EGR motor coils or associated circuit. The EGR system is continuously monitored for open, shorted to voltage, and shorted to ground faults in the four EGR motor coils, circuits, and the PCM. When a fault is detected, the EGR system is disabled and further monitoring is suspended for the remainder of the drive cycle until the next drive cycle. PCM P0404:00 EGR Control Circuit 'A' Range/Performance: no sub-type information Sets when the PCM detects that the EGR valve is in a position other than the commanded position. PCM P0405:00 EGR Sensor 'A' Circuit Low: no sub-type information Sets when the PCM detects that the average voltage at the PCM drops below the minimum calibrated voltage. The EGR monitor checks the EGR valve position sensor signal at the PCM for low voltage. PCM P0406:00 EGR Sensor 'A' Circuit High: no sub-type information Sets when the PCM detects that the average voltage at the PCM exceeds the maximum calibrated voltage. The EGR monitor checks the EGR valve position sensor signal at the PCM for high voltage. PCM P042E:00 EGR Valve 'A' Stuck Open: no sub-type information Sets when the PCM detects that the EGR commanded position is less than the threshold value, the actual EGR position is greater than the threshold value, and the EGR control limit is less than the specified limit. PCM P042F:00 EGR Valve 'A' Stuck Closed: no sub-type information This DTC sets when the EGR commanded position exceeds the threshold value, the actual EGR position is less than the threshold value, and the EGR control limit exceeds the specified limit. PCM P046D:00 EGR Sensor 'A' Circuit Intermittent/Erratic: no sub-type information Sets when the PCM detects that the average voltage at the PCM exceeds the maximum or minimum calibrated voltage. The EGR monitor checks the EGR valve position signal at the PCM for high and low voltage. PCM P04FA:00 EGR 'A' Control Temperature Too High: no sub-type information Sets when the PCM detects the EGR valve position and the position rate exceed the specified limit. PCM P1408:00 EGR Flow Out of Self-Test Range: no sub-type information VEHICLES WITH DPFEGR Sets when the PCM detects that the measured EGR flow falls above or below the required calibration. This test is performed only during KOEO self-test. The EGR system is commanded on at a fixed engine speed. VEHICLES WITH ELECTRIC EGR Sets when the PCM detects that the measured EGR flow falls above or below the required calibration. This test is performed only during KOEO self-test. The EGR system is commanded on at a fixed engine speed. Use the scan tool output state control function and monitor the MAP and EGRMDSD PIDs while commanding EGR on. If EGR is commanded on at idle, the engine speed drops or the engine stalls. Possible Sources EGR valve circuit problem MAP Sensor Mass air flow sensor Exhaust Gas Recirculation (EGR) Valve PCM (12A650)