DTC Troubleshooting

DTC Troubleshooting: P0718 (15)

DTC P0718: Input Shaft (Mainshaft) Speed Sensor Intermittent Failure

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review General Troubleshooting Information. How to Troubleshoot A/T Systems

- This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

1. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Test-drive the vehicle with the shift lever in D, at speeds over 12 mph (20 km/h), and let the transmission shift through all five gears.

4. Monitor the OBD STATUS for P0718 in the DTCs MENU with the HDS.

Does the HDS indicate FAILED?
YES - Go to step 5.

NO - If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals between the input shaft (mainshaft) speed sensor and the PCM. If the HDS indicates NOT COMPLETED, go to step 3.


5. Turn the ignition switch to LOCK (0).

6. Disconnect the input shaft (mainshaft) speed sensor connector, and inspect the connector and connector terminals to be sure they are making good contact.

Are the input shaft (mainshaft) speed sensor connector terminals OK?
YES - Go to step 7.

NO - Repair the connector terminals, then go to step 23.


7. Check for continuity between input shaft (mainshaft) speed sensor connector terminal No. 3 and body ground.

Is there continuity?
YES - Go to step 8.

NO - Repair open in the wire between the input shaft (mainshaft) speed sensor No. 3 and ground (G101), then go to step 20.






8. Turn the ignition switch to ON (II).

9. Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 1 and body ground.

Is there about 5 V?
YES - Go to step 10.

NO - Go to step 16.






10. Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.

Is there about 5 V?
YES - Replace the input shaft (mainshaft) speed sensor, A/T Input Shaft (Mainshaft) Speed Sensor Replacement (A/T) then go to step 20.

NO - Go to step 11.






11. Turn the ignition switch to LOCK (0).

12. Jump the SCS line with the HDS.

13. Disconnect PCM connector C (22P).

14. Check for continuity between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.

Is there continuity?
YES - Repair short to body ground in the wire between PCM connector terminal C19 and the input shaft (mainshaft) speed sensor, then go to step 20.

NO - Go to step 15.






15. Check for continuity between PCM connector terminal C19 and input shaft (mainshaft) speed sensor connector terminal No. 2.

Is there continuity?
YES - Go to step 26.

NO - Repair open in the wire between PCM connector terminal C19 and the input shaft (mainshaft) speed sensor, then go to step 20.






16. Turn the ignition switch to LOCK (0).

17. Jump the SCS line with the HDS.

18. Disconnect PCM connector A (31P).

19. Check for continuity between PCM connector terminal A20 and input shaft (mainshaft) speed sensor connector terminal No. 1.

Is there continuity?
YES - Go to step 26.

NO - Repair open in the wire between PCM connector terminal A20 and the input shaft (mainshaft) speed sensor, then go to step 20.






20. Reconnect all connectors.

21. Turn the ignition switch to ON (II).

22. Clear the DTC with the HDS.

23. Test-drive the vehicle with the shift lever in D, at speeds over 12 mph (20 km/h), and let the transmission shift through all five gears.

24. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0718 indicated?
YES - Check for poor connections or loose terminals between the input shaft (mainshaft) speed sensor and the PCM, then go to step 1.

NO - Go to step 25.


25. Monitor the OBD STATUS for P0718 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED?
YES - Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in step 24, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, check for poor connections or loose terminals between the input shaft (mainshaft) speed sensor and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, go to step 23.


26. Reconnect all connectors.

27. Update the PCM if it does not have the latest software, ECM/PCM Update or substitute a known-good PCM. Initial Inspection and Diagnostic Overview

28. Test-drive the vehicle with the shift lever in D, at speeds over 12 mph (20 km/h), and let the transmission shift through all five gears.

29. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0718 indicated?
YES - Check for poor connections or loose terminals between the input shaft (mainshaft) speed sensor and the PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then go to step 28. If the PCM was substituted, go to step 1.

NO - Go to step 30.


30. Monitor the OBD STATUS for P0718 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair If any other Temporary DTCs or DTCs were indicated in step 29, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, check for poor connections or loose terminals between the input shaft (mainshaft) speed sensor and the PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then go to step 28. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 28.