Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2011 GMC Yukon XL, 2011 GMC Yukon, 2011 Chevrolet Tahoe, 2011 Chevrolet Suburban, and 2011 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the camshaft position sensor and actuator magnet jumper harness connector. Refer to COMPONENT CONNECTOR END VIEWS - INDEX for connector identification.
- Ignition OFF for 1 minute, test for less than 5 Ω between the low reference circuit terminal E and ground.
- If greater than the specified value, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
- Ignition ON, engine OFF, verify that a test lamp does not illuminate between the control circuit terminal D and ground.
- If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
- Connect the DMM black lead to the control circuit terminal D. Connect the DMM red lead to B+. Set the DMM on the diode setting. Command the CMP actuator solenoid ON and OFF with a scan tool. The DMM should transition from OL when commanded OFF to less than 1 V when commanded ON.
- If the circuit voltage does not correspond to the specified values, test the control circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the ECM.
- Ignition OFF, test for infinite resistance between the control circuit terminal D and ground.
- If not the specified value, repair the control circuit for a short to ground.
- Test for 5.0-9.0 Ω between the control circuit terminal D and the low reference circuit terminal E.
- If less than the specified range, test for a short between the control circuit and the low reference circuit. If the circuits/connections test normal, test or replace the camshaft position actuator magnet.
- If greater than the specified range, test the control circuit and the low reference for an open/high resistance. If the circuits/connections test normal, test or replace the camshaft position actuator magnet.
- Remove the camshaft position actuator magnet. Perform the Camshaft Position Actuator Magnet Cleaning and Inspection
. The camshaft position actuator magnet should pass the inspection.
- If the inspection fails, replace the camshaft position actuator magnet.
- Perform the Camshaft Position Actuator Solenoid Valve Inspection (Off-Vehicle)
, Camshaft Position Actuator Solenoid Valve Inspection (On-Vehicle)
. The Camshaft Position Actuator Solenoid Valve should pass the inspection.
- If the inspection fails, replace the Camshaft Position Actuator Solenoid Valve.
- If all circuits and components test normal, replace the mechanical Camshaft Position Actuator.
NOTE:
Testing for steps 2-4 is performed on the ECM side of the jumper harness connector.
NOTE:
A test lamp must be used for this test. The control circuit is pulled-up to a low current voltage, A voltage on the control circuit is normal.
NOTE:
Testing for steps 5 and 6 is performed on the engine side of the jumper harness connector.