P0B09
Electric/Auxiliary Transmission Fluid Pump A Motor Supply Voltage Circuit/Open
Generic OBD-II
Common symptoms
What you'll notice
- Check the wiring and connections of the electric/auxiliary transmission fluid pump.
- Test the motor supply voltage circuit for any open circuits.
- Inspect the fuse related to the electric/auxiliary transmission fluid pump and replace if necessary.
- Verify that the motor supply voltage is reaching the electric/auxiliary transmission fluid pump.
- Replace the electric/auxiliary transmission fluid pump if all other solutions fail.
Common causes
Most likely first
- Loose or corroded electrical connections in the auxiliary/transmission fluid pump
- Faulty auxiliary/transmission fluid pump motor
- Blown fuse in the motor supply voltage circuit
- Damaged or faulty wiring in the motor supply voltage circuit
- Malfunctioning control module regulating the motor supply voltage
How to diagnose & fix
Work through it in order
- Erratic shifting or slipping of gears
- Delayed or harsh shifting of gears
- Illuminated check engine light
- Stalling or hesitation during acceleration
- Loss of power or reduced performance
Read & clear P0B09 yourself
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