P0939
Hydraulic Oil Temperature Sensor Circuit Low
Generic code
Transmission System
High severity
Hard repair
Free on OBD DashX
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What P0939 means
- The fault code P0939 indicates a low input signal detected in the hydraulic oil temperature sensor circuit. The hydraulic oil temperature sensor is responsible for monitoring the temperature of the hydraulic oil in the transmission. A low input signal suggests that the sensor circuit is not detecting the expected voltage or resistance, indicating a potential problem.
Possible symptoms
- Illuminated check engine light
- Inaccurate or inconsistent hydraulic oil temperature readings
- Abnormal transmission behavior or shifting issues
- Transmission overheating or fluid degradation
Possible causes
- Faulty hydraulic oil temperature sensor
- Short circuit or open circuit in the hydraulic oil temperature sensor circuit
- Wiring or connector issues in the sensor circuit
- Malfunctioning transmission control module (TCM)
Related parts
- Hydraulic Oil Temperature Sensor: Hydraulic oil is needed for the gear lubrication system. Hydraulic oil temperature sensor measures the temperature of the oil. This car's sensor has a problem which may cause difficulty in shifting gears
Possible solutions
- Inspect the hydraulic oil temperature sensor for any signs of damage or malfunction, and replace if necessary.
- Check the wiring and connections in the hydraulic oil temperature sensor circuit, and repair or replace as needed.
- Ensure the sensor is properly calibrated and positioned for accurate temperature readings.
- Verify the functionality of the transmission control module (TCM) and replace if necessary.
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P0939 on OBD DashX
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