RENR5042-02 133 Troubleshooting Section Repair: Temporarily connect a new sensor to the harness, but do not install the new sensor in the engine. Verify that there are no active diagnostic codes for the sensor. If there are no active diagnostic codes for the sensor, permanently install the new sensor. Clear any logged diagnostic codes. E. Measure the resistance between the terminal for the sensor signal wire at the ECM and engine ground. F. Turn the keyswitch to the OFF position. G. Reconnect P1 and P2. STOP. Expected Result: Not OK There is a short circuit between the sensor harness connector and the ECM. Leave the sensor disconnected. Proceed to Test Step 8.
Each resistance measurement is greater than 20,000 Ohms. Results: Test Step 5. Check the Pull-up Voltage at the Sensor Connector OK Each of the resistance measurements is greater than 20,000 Ohms. Proceed to Test Step 7. A. Turn the keyswitch to the ON position. B. Disconnect the suspect sensor. Not OK – At least one resistance measurement is less than 20,000 Ohms. C. Measure the voltage between terminal C (signal) and terminal B (sensor return) at the sensor connector. Repair: The low resistance measurement indicates a low resistance between two or more wires. Repair the connectors or wiring and/or replace the connectors or wiring. D. Turn the keyswitch to the OFF position. STOP.
Expected Result: Test Step 7. Create a Short at the Suspect Sensor Connector The voltage is 11 ± 2 VDC. Results: A. Turn the keyswitch to the OFF position. OK – The voltage is 11 ± 2 VDC. The signal wire to the ECM from the sensor connector is okay. B. Install a jumper wire with Deutsch sockets on each end between terminal B (sensor return) and terminal C (signal) on the connector for the suspect sensor. Connect the jumper on the harness side of the connector. Repair: The open circuit is in the sensor or the wire between the sensor and the sensor connector. Replace the sensor. Do not install the sensor in the engine.
Verify that no diagnostic codes are active for the suspect sensor before permanently installing the sensor. C. Turn the keyswitch to the ON position. D. Wait at least 15 seconds for activation of the short circuit diagnostic code 04. STOP. Note: Monitor the “Active Diagnostic Codes” screen on the electronic service tool before installing the jumper wire and after installing the jumper wire. Not OK The voltage is not 11 ± 2 VDC. The voltage is incorrect. Proceed to Test Step 6. Test Step 6. Check the Signal Wire for a Short Circuit E. Remove the jumper wire. F. Turn the keyswitch to the OFF position. A. Turn the keyswitch to the OFF position. B. Disconnect ECM connectors P1 and P2.
Expected Result: C. Disconnect the connector for the suspect sensor. A short circuit diagnostic code 04 is active when the jumper wire is installed. An open circuit diagnostic code 03 is active when the jumper wire is removed. D. Measure the resistance between the terminal for the sensor signal wire at the ECM and every terminal on ECM connector P1 and ECM connector P2. Results: OK – The engine harness and the ECM are okay.