Circuit/System Testing
- Ignition OFF, disconnect the CMP actuator solenoid harness connector at the CMP actuator solenoid.
- Test for less than 5 ohms between the low reference circuit terminal B and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance.
- Verify that a test lamp does not illuminate between the low reference circuit terminal B and the control circuit terminal A.
- If the test lamp illuminates, test the control circuit for short to voltage. If the circuit tests normal, replace the ECM.
- Remove the test lamp.
- Command the CMP Actuator Sol. ON with a scan tool. Verify the scan tool CMP actuator solenoid status is OK.
- If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
- Install a 3A fused jumper wire between the control circuit terminal A and the low reference circuit terminal B. Command the CMP Actuator Sol. ON with a scan tool. Verify the scan tool CMP actuator solenoid status is Fault.
- If not the specified value, test the control circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
- Determine that the vehicle has the correct engine oil. Refer to Service and Appearance Care in the owner's manual.
- If the engine oil life system monitor displays the Change Oil Soon message, the engine oil is more than one year old, contains additives, or is not the correct viscosity, change the oil.
- Test the engine oil pressure. Refer to Oil Pressure Diagnosis and Testing
.
- If the oil pressure is low, correct the low pressure first.
- Inspect each CMP actuator solenoid valve assembly for the following:
- Torn screens
- Debris on the screens
- Debris clogging the oil ports
- Missing screens
- Oil seepage at the solenoid connector pins
- Inspect for the following conditions:
- Excessive timing chain play
- Proper installation of the CMP actuator assembly
- If all circuits test normal, test or replace the CMP actuator solenoid.