2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1485

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1485

瀚慖f the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

2. Ignition OFF, disconnect the X2 harness connector at the G13 Generator.

3. Ignition ON, verify the scan tool Generator F-Terminal Signal parameter displays less than 5%.

瀚慖f greater than the specified range, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the K20

Engine Control Module.

4. Install a 3 A fused jumper wire between B+ and the signal circuit terminal 2.

5. Verify the scan tool Generator F-Terminal Signal parameter displays greater than 95%.

瀚慖f less than the specified range, test the signal circuit terminal 2 for a short to ground or an open/high resistance. If the circuit tests

normal, replace the K20 Engine Control Module.

6. If the circuit tests normal replace the G13 Generator.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Generator Replacement (LF1) (See: Starting and Charging/Charging System/Alternator/Service and Repair)Generator Replacement (LAU)

(See: Starting and Charging/Charging System/Alternator/Service and Repair)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup and programming

P0627

DTC P0627-P0629

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptors

DTC P0627

- Fuel Pump Enable Circuit

DTC P0628

- Fuel Pump Enable Circuit Low Voltage

DTC P0629

- Fuel Pump Enable Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) provides ignition voltage to the fuel pump flow control module whenever the engine is cranking or running. The

control module enables the fuel pump flow control module as long as the engine is cranking or running, and ignition system reference pulses are

received. While this enable voltage is being received, the fuel pump flow control module supplies a varying voltage to the in-tank fuel pump

module in order to maintain the desired fuel line pressure.

Conditions for Running the DTC

* The engine speed is greater than 0 RPM.

* The ignition voltage is between 11-18 V.

* The DTCs run continuously when the conditions above are met.

Conditions for Setting the DTC