What are the possible causes of the P129F code?
- Faulty fuel pump and level sensor assembly
- Fuel pump and level sensor wiring harness is open or short-circuited
- Poor electrical connection in the fuel pump and level sensor circuit
- Faulty fuel pump driver module
How to repair the P129F code?
Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and associated connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
What are the possible symptoms of the P129F code?
- Check engine light on (or Service Engine Soon warning light)
What does the P129F code mean?
The fuel pump driver control module sends reports of the actual fuel pump speed to the engine control module (ECM) as serial data every 10 ms. The ECM calculates the error between the commanded fuel pump speed and the fuel pump speed reported by the fuel pump driver control module. A diagnostic trouble code (DTC) will be set if the fuel pump speed is outside a calibrated threshold. The DTC will be set if the difference between the commanded fuel pump speed and the actual fuel pump speed is outside the calibrated range for more than 7 seconds.