P00A4 code meaning
Charge Air Cooler Temperature Sensor Circuit Intermittent/Erratic Bank 2
Powertrain system Generic code P00xx codes Check engine light
What P00A4 means
The charge air cooler temperature sensor for bank 2 (an NTC thermistor) measures the charge air temperature in the second charge-air path, for example on V engines with two charge air coolers. The engine control module uses it for the air mass calculation, boost control and component protection. For P00A4, the signal jumps faster than a real temperature can change, which typically points to a loose contact. No manufacturer description naming this exact code was found. Bank 2 codes occur only on engines with two separate intake or charge-air paths, one per cylinder bank.
P00A4 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of P00A4
- Check engine light on
- Usually no noticeable symptoms
- Emissions test or readiness check may fail
Common causes of P00A4
- Most likelyLoose contact or wire broken by movement
- PossibleSensor failing intermittently
- Less likelyInterference on the signal wire
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Charge air cooler temperature sensor bank2Charge air cooler temperature sensor wiring
What each part of P00A4 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 0 | Area: fuel and air metering and auxiliary emission controls. |
| A4 | The exact fault in that area. |
What to do next
- Note P00A4 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P00A4
What does P00A4 mean?
P00A4 means "Charge Air Cooler Temperature Sensor Circuit Intermittent/Erratic Bank 2". The charge air cooler temperature sensor for bank 2 (an NTC thermistor) measures the charge air temperature in the second charge-air path, for example on V engines with two charge air coolers. It is a generic code, so it means the same on every make.
Is it safe to drive with P00A4?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P00A4 fail an emissions test?
Yes, it can. P00A4 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P00A4 to fix?
Difficulty: easy. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P00A4 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.