Circuit/System Testing

With the key ON and the CMP sensor disconnected, measure the voltage between the 5-volt reference and a good ground and observe that the DMM measures 4.98-5.02 volts.
- If the DMM does not measure 4.98-5.02 volts, test the 5-volt reference for an open or high resistance. If the circuits test normal, replace the control module.
With the key ON and the CMP sensor disconnected, measure the voltage between the 5-volt reference circuit and the low reference circuit and observe that the DMM measures 4.98-5.02 volts.
- If the DMM does not measure 4.98-5.02 volts, test the low reference for an open or high resistance. If the circuits test normal, replace the control module.
With the key ON and the CMP sensor disconnected, connect a fused jumper wire to the signal circuit and momentarily and repeatedly probe the low reference circuit, and observe if the Cam Signal Present and Engine RPM parameters change.
- If the cam signal and engine RPM parameters do not change, test the signal circuit for an open, high resistance, a short to ground, a short to voltage. If the circuits test normal, replace the control module.
Ensure that the CMP sensor circuits are not routed too closely to the fuel injector wiring, after-market add-on electrical equipment, solenoids, relays, or motors.
Inspect the CMP sensor for physical damage, loose or improper installation, excessive air gap, or foreign material passing between the sensor and the reluctor wheel.
Inspect the CMP reluctor wheel for physical damage, improper installation, or excessive endplay or looseness.
If no other condition is found, replace the CMP sensor.