2010 Cadillac CTS Sedan AWD V6-3.6L Page 1134
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 scan tool DTC information, verify DTC P0627, P0628, P0629, P069E or U0109 is not set.
瀚慖f any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).
2. Engine idling, observe the scan tool Fuel Rail Pressure Sensor parameter. The pressure should be approximately 3.5-5.5 Mpa (508-798 psi).
3. Engine idling, the scan tool Fuel Rail Pressure Sensor should be close to the scan tool Desired Fuel Rail Pressure. As the engine speed
increases, the Desired Fuel Rail Pressure and the Fuel Rail Pressure Sensor should closely match each other.
4. Move related harnesses/connectors of the B47 fuel rail fuel pressure sensor and verify the engine does not stumble, stall, or change engine
speed.
瀚慖f the engine stumbles, stalls, or changes engine speed, test or repair the suspected harness or connection.
5. Observe the DTC information with a scan tool, DTC P0191 should not set.
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
1. Ignition OFF, disconnect the multi-way harness connector X117 at the rear of the intake manifold.
2. Remove the fuse that supplies B+ to terminal 56-X2 of the K20 ECM.
Note: Testing for steps 3 through 7 is performed on the ECM side of the multi-way harness connector.
3. Ignition OFF, test for less than 5 ohm between the low reference circuit terminal 5 and ground.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20
ECM.
4. Install the fuse that supplies B+ to terminal 56-X2 of the K20 ECM.
5. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 11 and ground.
瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal,
replace the K20 ECM.
瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
6. Ignition ON, verify the scan tool Fuel Rail Pressure Sensor voltage parameter is greater than 4.96 V.
瀚慖f less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
7. Connect a 3 A fused jumper wire between the signal circuit terminal 12 and the low reference circuit terminal 5. Verify the scan tool Fuel
Rail Pressure Sensor voltage parameter transitions from greater than 4.96 V to less than 0.02 V.
瀚慖f the parameter does not transition from the maximum to minimum value, test the signal circuit for an open/high resistance or a short to
voltage. If the circuit tests normal, replace the K20 ECM.
8. Ignition OFF, remove the intake manifold.
9. Connect the multi-way harness connector X117.
Note: Testing for steps 12 through 15 are performed at the fuel rail fuel pressure sensor connector.
10. Disconnect the B47 fuel rail fuel pressure sensor connector.
