P1255
DTC P1255 or P064A
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructionsprovides an overview of each diagnostic category.
DTC Descriptors
DTC P064A
- Fuel Pump Control Module Performance
DTC P1255
- Fuel Pump Control Module Driver Over-temperature
Circuit/System Description
The engine control module (ECM) supplies voltage to the fuel pump flow control module (FPCM) when the ECM detects that the ignition is on. The voltage from the ECM to the FPCM remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received, the FPCM supplies a varying voltage to the fuel tank pump module in order to maintain the desired fuel rail pressure.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
The FPCM detects an over-temperature fault.
Action Taken When the DTC Sets
DTCs P064A and P1255 are Type A DTCs.
Conditions for Clearing the DTC
DTCs P064A and P1255 are Type A DTCs.
Diagnostic Aids
Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
Fuel System Description Fuel System Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Programming and Relearningfor scan tool information
Circuit/System Testing
1. Verify that DTC P0231, P0232 or P023F are not set as current or history.
• If any of those codes are set, refer to DTC P0231, P0232, or P023F P0231.
2. Ensure that the entire undercarriage of the vehicle is clean, especially around the area where the FPCM is located. Clear all codes from the FPCM and test drive the vehicle. Verify that DTC P1255 or P064A do not set as current.
• If DTC P1255 or P064A reset as current, replace the FPCM.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Module References Programming and Relearningfor FPCM replacement, setup, and programming