Powertrain, generic · Fuel and air metering, auxiliary emission controls
P00A4 Charge Air Cooler Temperature Sensor Circuit Intermittent/Erratic Bank 2
Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo
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.
Likely causes
Loose contact or wire broken by movement
Sensor failing intermittently
Interference on the signal wire
Symptoms
- Check engine light on
- Usually no noticeable symptoms
- Emissions test or readiness check may fail
Repair estimate
DifficultyEasyDIY possible
Parts and labour€40–250
Time0.3–2 h
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
charge air cooler temperature sensor bank2charge air cooler temperature sensor wiring
Related codes
References: law.cornell.edu, static.nhtsa.gov, en.wikipedia.org.