2010 Cadillac CTS Sedan AWD V6-3.6L Page 794

2010 Cadillac CTS Sedan AWD V6-3.6L Page 794

4. Ignition ON, command the Fuel Pressure Regulator ON with a scan tool. Verify that the test lamp illuminates.

瀚慖f the test lamp does not illuminate, test the high control circuit for a short to ground or an open/high resistance. If the circuit tests normal,

replace the K20 ECM.

5. Ignition OFF, connect a test lamp between the low control circuit terminal 1 and B+.

6. Ignition ON, command the Fuel Pressure Regulator ON with a scan tool. Verify that the test lamp illuminates.

瀚慖f the test lamp does not illuminate, test the low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal,

replace the K20 ECM.

7. If all circuits test normal, test or replace the G18 high pressure fuel pump.

Component Testing

Static Test

1. Ignition OFF, disconnect the harness connector at the G18 high pressure fuel pump.

Note: The DMM and test leads must be calibrated to 0 ohm in order to prevent misdiagnosis.

2. Test for 9-11 ohm at 25掳C (77掳F) between the low control circuit terminal 1 and the high control circuit terminal 2.

瀚慖f not within the specified range, replace the G18 high pressure fuel pump.

3. Measure the resistance between each terminal and the high pressure fuel pump housing. The DMM should display OL.

瀚慖f less than the specified value, replace the G18 high pressure fuel pump.

Repair Instructions

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

* Fuel Pump Replacement (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel Pump/Service and Repair)

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

P00C9

DTC P0090-P0092, P00C8, P00C9, or P00CA (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 P0090

- Fuel Pressure Regulator Control Circuit

DTC P0091

- Fuel Pressure Regulator Control Circuit Low Voltage

DTC P0092

- Fuel Pressure Regulator Control Circuit High Voltage

DTC P00C8

- Fuel Pressure Regulator High Control Circuit

DTC P00C9

- Fuel Pressure Regulator High Control Circuit Low Voltage

DTC P00CA

- Fuel Pressure Regulator High Control Circuit High Voltage