2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1487
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM or fuel pump control module replacement, setup,
and programming
P0628
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
* The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match.
* The above condition is met for a minimum of 2.5 s.
Action Taken When the DTC Sets
DTCs P0627, P0628, and P0629 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0627, P0628, and P0629 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (LAU) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics
(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
