Faulty charge air cooler temperature sensor on Bank 2 (internal open circuit); Damaged, corroded or loose sensor connector or terminals; Open circuit or high resistance in the signal or ground wire between the sensor and the control unit; Signal wire shorted to a voltage supply; Wiring chafed or heat damaged near the intercooler pipework or exhaust; Fault in the engine control unit.

P00A3

Charge Air Cooler Temperature Sensor Circuit High Bank 2.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
0: AreaFuel and air metering, auxiliary emission controls
A3: FaultThe specific fault in that area

What it means

P00A3 means the engine control unit has detected a signal from the charge air cooler temperature sensor on Bank 2 that is higher than the expected range. This usually points to a sensor circuit fault, such as an open circuit or a short to voltage, rather than genuinely hot air. The exact sensor location and the Bank 2 layout depend on the engine, so check the manufacturer's information for the vehicle.

Symptoms

Engine warning light on
Reduced power or the engine going into limp mode
Poor acceleration or hesitant turbo boost response
Poor fuel economy
Rough running or irregular idle in some cases

Possible causes

Faulty charge air cooler temperature sensor on Bank 2 (internal open circuit)likely
Damaged, corroded or loose sensor connector or terminalslikely
Open circuit or high resistance in the signal or ground wire between the sensor and the control unitlikely
Signal wire shorted to a voltage supplypossible
Wiring chafed or heat damaged near the intercooler pipework or exhaustpossible
Fault in the engine control unitrare

How to diagnose

Read all stored and pending codes and the freeze frame data, noting engine temperature, load and ambient conditions when the fault was set.
Compare the Bank 2 charge air temperature reading in live data with the Bank 1 reading and intake air temperature on a cold engine; they should be similar.
Inspect the sensor, connector and wiring for damage, corrosion, moisture, chafing or heat damage, and check the connector locks properly.
Unplug the sensor and check live data: an open circuit commonly reads as the maximum value. Then check the sensor resistance against the manufacturer's specification at a known temperature.
With the ignition off and connector unplugged, test the signal and ground wires for continuity and for shorts to voltage or ground using a multimeter and the wiring diagram.
With the ignition on and the sensor unplugged, check the reference voltage and ground supply at the harness connector against the specification for the model.
Clear the codes and road test while watching live data to see if the fault returns, and check for wiring movement by gently flexing the harness.

How to fix

Replace the Bank 2 charge air cooler temperature sensor if its resistance or response is out of specification.
Clean or repair the connector and terminals, or replace the connector if it is damaged or corroded.
Repair or replace the open or high resistance wiring between the sensor and the control unit.
Repair any short to voltage in the harness and secure and protect the wiring away from heat and sharp edges.
Only after all wiring and sensor checks are complete, diagnose the control unit following the manufacturer's procedure.

Can I keep driving?

Medium severity

The car can usually be driven carefully for a short time, but power may be reduced and the control unit may limit boost. Get it checked soon, as the control unit can no longer monitor charge air temperature accurately.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.