What are the possible causes of the P129D Cadillac code?
- Faulty fuel pump power control module
- Fuel pump power control module harness is open or shorted
- Poor electrical connection in the fuel pump power control module circuit
How to repair the Cadillac 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 the P129D Cadillac code?
- Check Engine Light on (or Service Engine Soon warning light)
What does the Cadillac 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.