2010 Cadillac CTS Sedan AWD V6-3.0L Page 1530

2010 Cadillac CTS Sedan AWD V6-3.0L Page 1530

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

5. Verify the scan tool ECM GEN-F Terminal Signal parameter displays greater than 95 percent.

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

the K20 ECM.

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

(LSA) (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 (w/LF1)

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