P00A4
Charge Air Cooler Temperature Sensor Circuit Intermittent/Erratic Bank 2
Forced induction / air temperature
Generic OBD-II
Low
What it means
P00A4 means the computer is seeing an intermittent or erratic signal from the bank 2 charge-air-cooler (intercooler) temperature sensor, which measures the temperature of the compressed air after the intercooler. It usually points to a loose connector or chafed wiring rather than a failed sensor, and rarely affects how the car drives.
Low
Can I keep driving? Usually fine to drive — this is an intermittent sensor-signal fault; on a turbo/diesel the ECM may occasionally limit boost until it's fixed.
Common symptoms
What you'll notice
- Check-engine light on, sometimes coming and going
- Occasional stored code with no obvious driving change
- Possible brief loss of boost or reduced power on turbo/diesel engines
Common causes
Most likely first
- Loose, backed-out, or corroded connector at the charge-air-cooler (intercooler) temperature sensor on bank 2Likely
- Chafed or intermittently broken wiring in the sensor circuitCommon
- Failing charge-air-cooler temperature sensor with an erratic outputCommon
- Moisture or oil contamination in the sensor connectorLess often
- Rarely, an ECM/PCM faultLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data to see when the fault sets (cold, hot, over bumps).
- Locate the bank 2 charge-air-cooler (intercooler outlet) temperature sensor and inspect its connector for corrosion, spread pins, or looseness.
- Wiggle-test the harness and connector with the engine running to reproduce the intermittent signal.
- Check the sensor wiring for continuity and shorts against a known-good bank 1 reading.
- Replace the temperature sensor if the wiring and connector are good and the signal is still erratic. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P00A4?+
Generally yes. It's an intermittent air-temperature sensor signal, not a mechanical fault. On a turbocharged or diesel engine the computer may briefly reduce boost, so fix it if you notice power drops.
Can I just clear P00A4?+
You can, but an intermittent wiring or connector fault will return. Because it's erratic, focus on the connector and harness rather than immediately replacing the sensor.
Related codes
Read & clear P00A4 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX