Buick Regal: DTC P1007 or P129D

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 P1007

Fuel Pump Driver Control Module Ignition On/Start Switch Circuit High Voltage

DTC P129D

Fuel Pump Driver Control Module Ignition On/Start Switch Circuit Low Voltage

Diagnostic Fault Information

Circuit/System Description

The fuel pump driver control module monitors the ignition voltage circuit in order to determine if the voltage is within the normal operating range.

Conditions for Running the DTC

• Engine is cranking or running
• The powertrain sensor relay is commanded ON

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P1007

• The fuel pump driver control module ignition switch circuit voltage is greater than a calibrated value for 1 s.
• Requires 40 failures out of 50 samples at 0.05 s per sample.

P129D

The fuel pump driver control module ignition switch circuit voltage is less than a calibrated value for 1 s.

Action Taken When the DTC Sets

DTC P1007 and P129D are Type B DTCs.

Conditions for Clearing the DTC

DTC P1007 and P129D are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Description and Operation

Fuel System Description

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 Verification

1. Verify the engine cranks.

• If the engine does not crank

Refer to Starter Solenoid Does Not Click.

• Go to next step: If the engine cranks

2. Ignition ON.

3. Verify DTC P0562 or P0563 is not set.

• If DTC P0562 or P0563 is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: DTC P0562 or P0563 is not set

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

NOTE: Circuit/System Verification must be performed first or misdiagnosis may result.

1. Ignition OFF, all vehicle systems OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module. It may take up to 2 min for all vehicle systems to power down.

2. Ignition ON.

3. Verify a test lamp illuminates between the ignition circuit terminal 17 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp.
2. Test for less than 2 Ω in the ignition circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp.
2. Test for infinite resistance between the ignition circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If the test lamp illuminates

4. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min for all vehicle systems to power down.

5. Verify a test lamp does not illuminate between the ignition circuit terminal 17 and ground.

• If the test lamp illuminates

Repair the short to voltage on the circuit.

• Go to next step: If the test lamp does not illuminate

6. Replace the K111 Fuel Pump Driver Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Refer to Control Module References for control module replacement, programming and setup.

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