P0939moderate severityPowertrain
Hydraulic Oil Temperature Sensor Circuit High
on 2003 Audi A6 3.0L V6 · AWD
What this code means
The hydraulic oil temperature sensor signal is higher than expected. This is typically due to a wiring short or defective sensor.
Symptoms
- Transmission warning light on
- Erratic shifting
- False overheat indication
Common causes
- Faulty oil temperature sensor
- Short to voltage in circuit
- Corroded connector pins
- Bad transmission control module
Diagnostic steps
- Scan for stored codes
- Inspect connector for damage
- Check circuit for short to voltage
- Verify sensor signal against spec
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