Electric/Auxiliary Transmission Fluid Pump A Motor Current Low
What it means
The motor of electric auxiliary transmission fluid pump A is drawing too little current. This pump circulates transmission fluid, and the control module watches its current to spot a worn, blocked or failing pump.
Can I keep driving? Usually drivable in the short term, but low transmission fluid flow can overheat the transmission, so get it read soon.
What this part does
The auxiliary electric transmission fluid pump supplies transmission fluid pressure when the engine is stopped, such as during an engine start-stop event or while a hybrid runs on electric power. The transmission control module switches it on so clutches stay filled and shifts stay smooth. Some designs work with high voltage, where service is for trained people. A fault can cause delayed engagement or rough starts from rest.
Common symptoms
What you'll notice
- Loss of power or acceleration
- Transmission slipping or shifting issues
- Overheating of the transmission
- Warning light on the dashboard
- Strange noises coming from the transmission
Common causes
Most likely first
- Faulty electric or auxiliary transmission fluid pump motor
- Low transmission fluid level
- Blocked or damaged transmission fluid lines
- Faulty transmission control module
- Faulty transmission fluid pressure sensor
How to diagnose & fix
Work through it in order
- Check the wiring and connections of the electric/auxiliary transmission fluid pump
- Inspect the motor of the electric/auxiliary transmission fluid pump for any signs of damage or malfunction
- Test the motor current of the electric/auxiliary transmission fluid pump to ensure it is operating within the correct range
- Replace the electric/auxiliary transmission fluid pump if it is found to be faulty or not functioning properly
Related codes
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