What are the possible causes of GMC P129B code?
- Faulty fuel pump driver control module
- Fuel pump driver control module harness is open or shorted
- Poor electrical connection in fuel pump driver control module circuit
How to repair GMC P129B 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 P129B code?
- Check Engine Light illuminated (or Service Engine Soon warning light)
What does GMC P129B code mean?
The fuel pump power control module monitors the battery positive voltage circuit to verify that the voltage is within the normal operating range. The Diagnostic Trouble Code (DTC) will be set when the fuel pump power control module detects that the battery positive voltage is below 7 V for 1 second.