P0549moderate severityPowertrain
Exhaust Gas Temperature Sensor Circuit High (Bank 2 Sensor 1)
on 2009 Audi Q7 3.0L Supercharged V6 · AWD
What this code means
The PCM detected a high voltage signal from the bank 2 exhaust gas temperature sensor. This sensor monitors exhaust heat to protect turbo and aftertreatment parts.
Symptoms
- Check engine light on
- Reduced engine power
- Possible limp mode
Common causes
- Faulty exhaust gas temperature sensor
- Open in sensor wiring
- Corroded or loose connector
- Failed PCM input circuit
Diagnostic steps
- Read bank 2 sensor data with scan tool
- Inspect wiring for opens
- Measure sensor resistance and signal
- Compare with known good temperature reading
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