P0038low severityPowertrain
HO2S Heater Control Circuit High Bank 1 Sensor 2
on 2010 BMW M3 E90 4.0L V8 S65 · RWD
What this code means
The voltage in the Bank 1 Sensor 2 O2 heater circuit is higher than expected.
Symptoms
- Check Engine Light
- Possible overheating
Common causes
- Short to power
- Faulty sensor
- Relay issue
Diagnostic steps
- Test heater voltage
- Check for shorts to power
- Test resistance
Repair notes
Repair short or replace sensor.
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