2010 Cadillac CTS Sedan AWD V6-3.6L Page 985
Fuel System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Fuel System Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
1. Observe the DTC information with a scan tool. DTC P029D, P02A1, P02A5, P02A9, P02AD, P02B1, P0627, P0628, P0629, P069E, or
U0109 should not set.
瀚慖f a DTC is set refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble
Code (DTC) List - Vehicle).
2. Attempt to start and idle the engine.
3. Observe the DTC information with a scan tool. DTCs P0087, P0088, and P0089 should not set.
4. Engine idling, observe the Fuel Rail Pressure Sensor parameter with a scan tool. The pressure should be approximately 3.5-5.5 Mpa (508-798
psi).
5. Command an increase and decrease in fuel rail pressure with a scan tool. Observe the scan tool Fuel Rail Pressure Sensor parameter. The
Fuel Rail Pressure Sensor should increase or decrease with each commanded state.
6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Note: Circuit/System Verification must be performed first or misdiagnosis may result.
1. Ignition ON, observe the scan tool fuel pump control module fuel line pressure sensor parameter. Command an increase in the fuel line
pressure with a scan tool. Verify the fuel line pressure increases to greater than 414 kPa (60 psi) as commanded.
瀚慖f the less than the specified range, refer to Fuel System Diagnosis (See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel System Diagnosis).
Note: As little as 2 ohm on either circuit of the high pressure fuel pump actuator will cause these DTCs to set. Test the circuits of the high
pressure fuel pump actuator for a high resistance if you suspect a condition.
2. Remove the G18 high pressure fuel pump and visually inspect the lobes on the camshaft for unusual wear.
瀚慖f the lobes appear normal, replace the G18 high pressure fuel pump.
瀚慖f the lobes are worn, replace the camshaft.
Component Testing
Static Test
1. Ignition OFF, disconnect the harness connector at the high pressure fuel pump.
Note: The DMM and test leads must be calibrated to 0 ohm in order to prevent misdiagnosis.
2. Test for 0.35-0.6 ohm at 20掳C (68掳F) of resistance between low control circuit terminal 1 and high control circuit terminal 2.
瀚慖f the resistance is less than 0.3 ohm or greater than 0.6 ohm, replace the high pressure fuel pump.
3. Test for infinite resistance between each terminal and the high pressure fuel pump housing/case.
瀚慖f not the specified value, replace the high pressure fuel pump.
