Fuel and air

P00A1 — Charge Air Cooler Temperature Sensor Range/Performance, Bank 2

Severity: medium Drive with care, to a shop

What P00A1 means

The engine control module compares the bank 2 charge air cooler (intercooler) temperature signal with what it expects based on load, intake air temperature, and other sensors. If the reading is unrealistic, stuck, or responds too slowly, it sets P00A1. The ECM uses this temperature to adjust boost, fueling, and spark timing to protect the engine.

Symptoms

  • Check Engine light on
  • Reduced power and sluggish acceleration
  • Worse fuel economy
  • Limp or failsafe mode
  • Possible inhibited DPF regeneration on diesels

Possible causes

  1. Failed bank 2 charge air cooler temperature sensor
  2. Damaged or corroded wiring or connector in the sensor circuit
  3. Open circuit or short to ground or power in the harness
  4. Clogged intercooler or boost air leaks
  5. Rarely, a faulty ECM

How to diagnose

  1. Scan all codes and freeze frame data and look for other boost or temperature sensor codes
  2. Inspect the sensor, connector, and harness for oil, corrosion, chafing, or a loose fit
  3. On a cold engine, compare the sensor reading with intake air and coolant temperature; they should be close
  4. Check reference voltage and ground at the sensor connector with a multimeter
  5. Measure sensor resistance and compare it to the manufacturer's chart at a known temperature
  6. Test the wiring to the ECM for opens and shorts
  7. Inspect the intercooler and hoses for leaks, oil, or blockage, and pressure test the boost system if needed

Common fixes

  • Replace the bank 2 charge air temperature sensor
  • Repair the wiring or replace the damaged connector
  • Fix leaks, replace cracked hoses or clamps, and clean or replace the intercooler
  • Update software or replace the ECM if everything else checks out

Questions and answers

What does P00A1 mean?

The ECM found that the bank 2 intercooler temperature sensor signal is outside the expected range or behavior. The sensor or its wiring is the most common culprit.

Can I drive with P00A1?

Briefly and carefully, for example to a repair shop. Power may be limited, and longer driving raises fuel use and engine stress.

How do I fix P00A1?

Start by checking the sensor connector and harness, then the sensor itself and the intercooler and hoses for leaks. Replacing the sensor or repairing the wiring usually solves it.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.