DTC P025A
DTC P025A |
Diagnostic Instructions |
• |
Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
|
• |
Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
|
• |
Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
|
DTC Descriptor |
DTC P025A
Fuel Pump Control Module Enable Circuit
Diagnostic Fault Information |
Circuit | Short to Ground | Open or High Resistance | Short to Voltage | Signal Performance |
FPCM Control | P025A | P025A | - | P025A |
Circuit/System Description |
The engine control module (ECM) supplies voltage to the fuel pump control module when the ECM detects that the ignition is on. The voltage from the ECM to the fuel pump control module remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received, the fuel pump control module 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 ignition is ON.
Conditions for Setting the DTC |
The serial data message from the ECM to the fuel pump control module does not agree with the state of the control enable voltage signal supplied from the ECM to the fuel pump control module for more than 2 seconds.
Action Taken When the DTC Sets |
DTC P025A is a Type A DTC.
Conditions for Clearing the DTC |
DTC P025A is a Type A DTC.
Reference Information |
Schematic Reference
Engine Controls Schematics (3.0L (LF1)) Engine Controls Schematics (2.8L (LAU))
Connector End View Reference
Component Connector End Views
Description and Operation
Fuel System Description (LF1) Fuel System Description (LAU or LY7)
Electrical Information Reference
• |
Circuit Testing
|
• |
Connector Repairs
|
• |
Testing for Intermittent Conditions and Poor Connections
|
• |
Wiring Repairs
|
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing |
1. |
Ignition OFF, disconnect the harness connector at the K27 fuel pump control module.
|
2. |
Ignition OFF, connect a test lamp between the control circuit terminal 20 and ground.
|
3. |
Ignition ON, command the ECM fuel pump enable command ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
|
4. |
If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
|
5. |
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 K20 ECM.
|
6. |
If all circuits test normal, replace the K27 fuel pump control module.
|
Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ECM or fuel pump control module replacement, setup, and programming