What it means
The auxiliary transmission fluid pump A motor reports temperature above the protection threshold. Sustained high load or cooling failure.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Auxiliary transmission fluid pump A circulates transmission fluid when the vehicle's transmission control strategy calls for it. This code sets when the pump A motor temperature exceeds its protection threshold, which can happen under excessive load or when cooling and fluid conditions are inadequate.
Common causes
Most likely first.
- Faulty or mechanically overloaded auxiliary transmission fluid pump
- Low or degraded transmission fluid
- Pump wiring or connector fault
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Save freeze-frame data and transmission codes, then note pump A motor temperature, operating state, and when the temperature rises.
- Check the transmission fluid level and condition using the manufacturer's procedure, since low or degraded fluid can increase pump load or impair cooling.
- Inspect pump A wiring and connector for damage, poor connections, or signs of overheating.
- Check whether the pump operates and circulates fluid as commanded, using the manufacturer's diagnostic procedure.
- If fluid and wiring checks pass, test pump A for mechanical drag or motor failure and verify its temperature sensing and control.
Common fixes
- Correct the transmission fluid level or condition using the specified fluid and service procedure.
- Repair a damaged or loose pump A connector or wiring.
- Replace auxiliary transmission pump A if it is overloaded or failing.
- Repair a failed pump temperature sensing or control component identified by testing.
Can I keep driving?
Avoid driving if shifts are slipping, harsh, delayed, or missing, or if the transmission warning appears with reduced power; overheating can damage the transmission. If symptoms are mild, drive only a short distance gently to a safe place for diagnosis.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.