P0939
PowertrainTransmission Pressuremoderate severityHydraulic Oil Temperature Sensor Circuit High
What P0939 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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