OBD-II code · Powertrain (generic)
P0B09 Electric/Auxiliary Transmission Fluid Pump A Motor Supply Voltage Circuit/Open
The supply voltage circuit of auxiliary transmission fluid pump A motor reports a open condition.
Is it safe to drive with P0B09?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyOpen in supply wire
- PossibleSupply fuse blown
- Less likelyPin pushed back out of connector body
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
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Usually unaffected
- Parts involved
- Aux Trans Pump A Motor, Wiring Harness, Tcm
Related codes
- P0B06Electric/Auxiliary Transmission Fluid Pump Motor Phase W Current
- P0B07Electric/Auxiliary Transmission Fluid Pump Motor Phase W Current Low
- P0B08Electric/Auxiliary Transmission Fluid Pump Motor Phase W Current High
- P0B0AElectric/Auxiliary Transmission Fluid Pump A Motor Supply Voltage Circuit Low
- P0B0BElectric/Auxiliary Transmission Fluid Pump A Motor Supply Voltage Circuit High
- P0B0CElectric/Auxiliary Transmission Fluid Pump A Hydraulic Leakage
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.