Auxiliary Transmission Fluid Pump Control Module Circuit Low
The P0C24 code indicates that the control module for the auxiliary transmission fluid pump has detected a low voltage or resistance in its circuit. This pump is typically used in hybrid or electric vehicles to circulate transmission fluid when the main engine is off, ensuring proper lubrication and cooling. A low circuit condition can be caused by a faulty pump module, damaged wiring, poor electrical connections, or a blown fuse. This issue may lead to inadequate transmission fluid circulation, potentially causing transmission overheating or damage.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission overheating or slipping
- Reduced fuel economy in hybrid mode
- Unusual noises from the transmission area
2. Most Common Causes
- Short to ground in the auxiliary pump control module circuit wiring
- Loose or corroded connections in the module wiring harness
- Excessive circuit resistance due to damaged wires or poor splices
- Internal failure of the auxiliary transmission fluid pump control module
- Insufficient or unstable voltage supply to the control module
- Faulty ECM/PCM (less common)
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for related codes.
Step 2: Visually inspect the auxiliary pump wiring and connectors for damage or corrosion.
Step 3: Test the pump control module power and ground circuits with a multimeter.
Step 4: Check the fuse and relay for the auxiliary pump; replace if blown.
Step 5: If circuits are intact, test the pump module per manufacturer specifications; replace if faulty.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances, as the auxiliary pump may fail to lubricate the transmission, leading to 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 issue is a simple wiring repair or a full pump module replacement. Labor and parts vary by vehicle make and model.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.