P1255 GMC Possible Causes
- Faulty fuel pump control module
- Fuel pump control module harness is open or shorted
- Poor electrical connection in the fuel pump control module circuit
How is GMC P1255 Code Repaired?
Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Engine light on (or service engine soon warning light)
P1255 GMC Meaning
The Engine Control Module (ECM) provides voltage to the fuel pump control module when the ECM detects that the ignition is turned on. The voltage from the ECM to the fuel pump control module remains active for 2 seconds, unless the engine is running or cranking. While this voltage is being received, the fuel pump control module provides variable voltage to the fuel tank pump module to maintain the desired fuel pressure. The Diagnostic Trouble Code (DTC) will be set if the fuel pump control module detects an overheating fault.