The P0B09: Auxiliary Transmission Fluid Pump Motor Supply Voltage Circuit/Open refers to a problem where there is an open circuit or a lack of supply voltage to the auxiliary transmission fluid pump motor. This may be caused by faulty wiring, a bad connection, or a defective motor. If not addressed, it can prevent the transmission fluid pump from functioning properly, leading to potential overheating or damage to the transmission.
P0B09 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0B09: Auxiliary Transmission Fluid Pump Motor Supply Voltage Circuit/Open |
| Is it serious? | Yes, this may lead to transmission fluid pump failure or overheating. |
| Possible causes | – Open circuit in the auxiliary transmission fluid pump motor supply voltage – Faulty wiring or connection – Defective auxiliary transmission fluid pump motor |
| How to diagnose? | – Check for open circuit in the motor supply voltage – Inspect wiring and connections – Test the auxiliary transmission fluid pump motor |
P0B09 Meaning
The P0B09 code indicates that the auxiliary transmission fluid pump motor is experiencing an open circuit or a supply voltage issue. This could be due to faulty wiring, poor connections, or a defective motor, which prevents the pump from receiving adequate power to operate.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional codes that may give further insight into the issue. | OBD-II Scanner |
| Check for Open Circuit | Use a multimeter to check for an open circuit in the motor’s supply voltage circuit. | Multimeter |
| Inspect Wiring and Connections | Visually inspect the wiring and connections for any signs of wear, corrosion, or disconnection. | Flashlight, Multimeter, Safety Gloves |
| Test the Auxiliary Transmission Fluid Pump Motor | Test the motor to ensure it is functioning correctly and replace if needed. | Multimeter, Diagnostic Tool |
| Clear the Code and Test Drive | After repairs, clear the code and take the vehicle for a test drive to ensure the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Rescan the vehicle to confirm that the P0B09 code does not reappear after the test drive. | OBD-II Scanner |
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I test OBD-II scanners and make DIY Engine diagnostics guides to help you solve your car problems without having to depend on the mechanic. A lot of them will try to scam you or are just no help at all. About Juraj Lukacko