Auxiliary Transmission Fluid Pump Control Module Internal Temperature Sensor Circuit High
The P0C1F code indicates that the internal temperature sensor circuit within the auxiliary transmission fluid pump control module is reading a voltage higher than the expected range. This sensor monitors the temperature of the control module to prevent overheating. A high voltage reading typically suggests a short to power, a faulty sensor, or an internal module failure. This can lead to improper pump operation, affecting transmission cooling and lubrication, especially in hybrid or electric vehicles with auxiliary pumps.
01. Most Common Causes
- Short to battery voltage in the temperature sensor circuit
- Faulty internal temperature sensor within the control module
- Damaged auxiliary transmission fluid pump control module
- Corroded or damaged wiring/connectors in the sensor circuit
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission performance issues (e.g., harsh shifting, slipping)
- Reduced fuel economy
- Possible transmission overheating
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to retrieve all stored codes and freeze frame data.
Step 2: Visually inspect the auxiliary transmission fluid pump and its wiring/connectors for damage, corrosion, or loose connections.
Step 3: Test the temperature sensor circuit voltage at the control module connector using a multimeter. Compare with manufacturer specifications.
Step 4: If voltage is high (e.g., >5V), check for a short to power. If voltage is within range but code persists, suspect a faulty control module.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as it can lead to transmission overheating and potential damage. Have the vehicle inspected promptly.
How much does it cost to fix?▼
Repair costs typically range from $200 to $600, depending on whether the control module needs replacement and labor rates.