Circuit/System Testing
- Ignition OFF, disconnect the harness connector of the CMP sensor.
- Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit and ground.
- If the test lamp does not illuminate, test the ignition 1 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition 1 voltage circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary.
- Connect a test lamp between the ground circuit and the ignition 1 voltage circuit. Verify the test lamp illuminates.
- If the test lamp does not illuminate, repair the open/high resistance on the ground circuit.
- Ignition ON, test for 4.8-5.2 volts between the signal circuit and the ground circuit.
- If less than 4.8 volts, test the signal circuit for a short to ground or an open/high resistance. If the circuits/connections test normal, replace the ECM.
- If greater than 5.2 volts, test the signal circuit for a short to voltage. If the circuits/connections test normal, replace the ECM.
- If all circuits/connections test normal, replace the CMP sensor.