P0232

DTC P0231, P0232, or P023F

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 Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0231
- Fuel Pump Control Circuit Low Voltage

DTC P0232
- Fuel Pump Control Circuit High Voltage

DTC P023F
- Fuel Pump Control Circuit

Diagnostic Fault Information






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 two 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 pressure.

Conditions for Running the DTC

P0231, P023F

The ignition voltage is between 9-18 V.

P0232

The control enable voltage signal supplied for the ECM to FPCM is inactive for 4 seconds after engine has been shut off.

Conditions for Setting the DTC

The FPCM detects a fault on the fuel pump voltage circuit that is above or below a predetermined voltage threshold.

Action Taken When the DTC Sets

DTCs P0231, P0232, and P023F are Type A DTCs.

Conditions for Clearing the DTC

DTCs P0231, P0232, and P023F 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.

On vehicles equipped with a high pressure mechanical pump on Direct Fuel Injection engines, the vehicle may continue to run even though the pump in the fuel tank is not operating.

Reference Information

Schematic Reference

Engine Controls Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views A/C Compressor Clutch

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 Relearning for scan tool information

Circuit/System Verification

Ignition ON, command the fuel pump ON and OFF using the scan tool ECM fuel pump output control. The fuel pump should turn ON and OFF.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the fuel pump.

2. Connect a test lamp between the control circuit terminal 1 and ground.

3. Ignition ON, command the fuel pump ON and OFF using a scan tool ECM fuel pump output control. The test lamp should turn ON and OFF as commanded.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the FPCM.

• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the FPCM.

4. Ignition OFF, connect a test lamp between the control circuit terminal 2 and the control circuit terminal 1.

5. Ignition ON, command the fuel pump ON using a scan tool. The test lamp should illuminate.

• If the test lamp does not illuminate, test the control circuit terminal 2 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the FPCM.

6. If all circuits test normal, replace the fuel tank fuel pump module.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Fuel Tank Module Replacement Service and Repair

* Control Module References Programming and Relearning for FPCM replacement, programming and setup