P0946
PowertrainTransmission Pressuremoderate severityHydraulic Pump Relay Circuit Range/Performance
What P0946 Means
The hydraulic pump relay circuit is reading a value outside the expected range. The signal is present but not performing as the PCM expects.
Symptoms
- Erratic shifting
- Transmission warning light on
- Intermittent transmission problems
Common Causes
- Failing hydraulic pump relay
- Poor electrical connection or corrosion
- Damaged relay circuit wiring
- Faulty PCM/TCM
Diagnostic Steps
- Inspect relay and connector for corrosion
- Monitor relay circuit voltage with scan tool
- Test relay under load
- Check wiring for high resistance
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