P0857moderate severityPowertrain
Traction Control Input Signal Range/Performance
on 2002 Audi A6 3.0L V6 · AWD
What this code means
The PCM receives a traction control input signal that is out of the expected range or performance limits. This may cause traction and stability systems to behave incorrectly.
Symptoms
- Traction control warning light
- Stability control disabled
- Intermittent engine power loss
Common causes
- Faulty wheel speed or traction sensor
- CAN signal noise or interference
- Failed traction control module
- Wiring or connector fault
Diagnostic steps
- Scan PCM and ABS for codes
- Review data stream for signal range
- Inspect wiring and sensor connectors
- Replace faulty sensor or module
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