What are the possible causes of GMC P129D code?
- Faulty fuel pump power control module
- Fuel pump power control module harness is open or shorted
- Poor electrical connection in fuel pump power control module circuit
How to repair GMC P129D code?
Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
What are the possible symptoms of GMC P129D code?
- Engine light on (or Service Engine Soon warning light)
What does GMC P129D code mean?
The fuel pump power control module monitors the ignition voltage circuit to determine if the voltage is within the normal operating range. The diagnostic trouble code (DTC) will be set when the voltage of the fuel pump power control module ignition switch circuit is below a calibrated value for 1 second.