P0944high severityPowertrain
Hydraulic Pressure Unit Loss of Pressure
on 2005-2011 Audi A6 4.2L V8 · AWD
What this code means
The transmission hydraulic system has lost pressure. This usually indicates a major leak, a failed pump, or a stuck valve preventing proper pressure buildup.
Symptoms
- Transmission slipping
- No shifting or stuck in gear
- Transmission warning light on
Common causes
- Faulty hydraulic pump
- Major internal transmission leak
- Low transmission fluid
- Stuck pressure control valve
Diagnostic steps
- Check transmission fluid level and condition
- Test line pressure with a gauge
- Inspect for internal and external leaks
- Test pump and pressure control solenoid operation
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