What does it mean?
This code applies the same plausibility check as its bank 1 counterpart, but to the bank 2 side of a forced induction engine. The charge air cooler temperature sensor on that bank measures the air leaving the intercooler, and the intake air temperature sensor measures air entering the induction system. After a long soak neither is being heated, so their readings should be within a few degrees of each other and of ambient temperature. The module stores the code when the difference at the first key on exceeds the calibrated tolerance, telling you that one of the two sensors on that bank has drifted or is not sitting in the air stream it is supposed to measure.
Symptoms
- MIL on, typically after a cold soak rather than during driving
- Reduced boost and a duller response on that bank as the module applies a protective calibration
- Charge air temperature for bank 2 that does not follow the other intake readings
- Slight loss of power and higher fuel consumption
- Knock or pinging under load on gasoline engines
- Smoke or hesitation under load on diesels
Likely causes
- Bank 2 charge air cooler temperature sensor drifted or coated with oil and soot
- Intake air temperature sensor drifted or reading high because of heat soak at its mounting position
- High resistance in the signal or ground circuit of either sensor
- Sensor loose in its port, or an air leak letting hot engine bay air reach the tip
- Wrong replacement sensor with a different resistance curve fitted to that bank
- Oil carried into the bank 2 intercooler by a failing crankcase ventilation system
- Corroded or damaged terminal at the module connector for that input
How to fix it
- Compare both bank 2 readings with a measured ambient temperature after an overnight soak
- Cross check with an infrared thermometer at the bank 2 intercooler outlet and the intake duct while cold
- Measure each sensor resistance or signal voltage against its temperature curve
- Inspect the sensor tip and the bank 2 intercooler for oil film and soot, and check that the sensor is fully seated
- Test the reference and ground circuits for voltage drop and inspect connectors for corrosion
- Repair the source of any oil carry over, then re-evaluate the readings
- Replace only the sensor proven to be wrong and repeat the comparison after another cold soak