The P0C29: Auxiliary Transmission Fluid Pump Driver Circuit Performance fault code indicates an issue with the performance of the driver circuit for the auxiliary transmission fluid pump. This can be caused by faulty driver components, wiring problems, or poor connections. The driver circuit controls the operation of the pump, and any performance issues can affect the cooling of the transmission fluid.
P0C29 – Quick Overview
Code | Information |
---|---|
Meaning | P0C29: Auxiliary Transmission Fluid Pump Driver Circuit Performance |
Is it serious? | Yes, driver circuit issues can cause improper pump function, leading to transmission cooling problems. |
Possible causes | – Driver circuit performance issues – Faulty driver components – Wiring or connection problems |
How to diagnose? | – Verify the driver circuit performance – Test driver components – Inspect wiring and connections |
P0C29 Meaning
The P0C29 code indicates that the driver circuit controlling the auxiliary transmission fluid pump is not performing within expected parameters. This could be due to internal driver component failures, wiring issues, or poor connections. The driver circuit plays a critical role in regulating the pump’s operation, ensuring proper transmission fluid circulation and cooling.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any additional related codes that may provide further context, especially regarding driver circuits or electrical system faults. | OBD-II Scanner |
Verify Driver Circuit Performance | Use a multimeter or diagnostic tool to measure the performance of the driver circuit. Compare the readings with manufacturer specifications to ensure the circuit is functioning properly. | Multimeter, Diagnostic Tool |
Test Driver Components | Test the components responsible for driving the auxiliary transmission fluid pump (e.g., transistors, relays, control modules) to ensure they are operating within normal parameters. | Diagnostic Tool, Component Tester |
Inspect Wiring and Connections | Visually inspect the wiring and connectors for any signs of damage, corrosion, or loose connections that could cause performance issues in the driver circuit. Repair or replace as necessary. | Flashlight, Multimeter, Wiring Diagram |
Check the Control Module | If the driver circuit and components are functioning properly, inspect the control module for internal faults that could be affecting the circuit’s performance. | Diagnostic Tool, Vehicle Manual |
Clear the Code and Test Drive | After repairs, clear the fault code using an OBD-II scanner and perform a test drive to ensure that the driver circuit is performing correctly and the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the system to confirm that the P0C29 code does not return. | OBD-II Scanner |

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