Auxiliary Transmission Fluid Pump Performance Issue
The P2797 code indicates that the auxiliary transmission fluid pump, which is typically used in start-stop systems to maintain transmission pressure when the engine is off, is not performing as expected. This can lead to delayed engagement or transmission damage if not addressed.
01. Most Common Causes
- Faulty auxiliary transmission fluid pump
- Low transmission fluid level
- Wiring or connector issues in the pump circuit
- Faulty transmission control module (TCM)
02. Symptoms You Will Notice
- Delayed transmission engagement after engine restart
- Transmission slipping or harsh shifting
- Check Engine Light illuminated
- Start-stop system malfunction
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and check freeze frame data.
Step 2: Inspect transmission fluid level and condition; top off or replace if necessary.
Step 3: Test the auxiliary pump electrical circuit for voltage, ground, and resistance.
Step 4: If circuit is OK, replace the auxiliary transmission fluid pump.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause transmission damage. Limited driving to a repair shop is acceptable.
How much does it cost to fix?▼
Repair costs typically range from $200 to $600, including parts and labor, depending on the vehicle and pump location.