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 (A/T)

- 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, and let the transmission shift through all five gears at speeds over 12 mph (20 km/h).

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 connector terminals OK?
YES - Go to step 7.

NO - Repair the connector terminals, then go to step 24.


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

8. Jump the SCS line with the HDS.

9. Disconnect PCM connector C (44P).

10. Check for continuity between PCM connector terminal C40 and body ground, and between terminal C44 and body ground.

Is there continuity?
YES - Go to step 11.

NO - Repair open in the wires between PCM connector terminals C40, C44, and body ground (G101), or repair poor body ground (G101), then go to step 24.






11. Connect PCM connector C (44P).

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

13. 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 18.

NO - Go to step 14.






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

15. Jump the SCS line with the HDS.

16. Disconnect PCM connector B (44P).

17. Check for continuity between PCM connector terminal B18 and input shaft (mainshaft) speed sensor connector terminal No. 1.

Is there continuity?
YES - Go to step 30.

NO - Repair open in the wire between PCM connector terminal B18 and the input shaft (mainshaft) speed sensor, then go to step 24.






18. 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, Service and Repair then go to step 24.

NO - Go to step 19.






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

20. Jump the SCS line with the HDS.

21. Disconnect PCM connector B (44P).

22. Check for continuity between PCM connector terminal B17 and input shaft (mainshaft) speed sensor connector terminal No. 2.

Is there continuity?
YES - Go to step 23.

NO - Repair open in the wire between PCM connector terminal B17 and the input shaft (mainshaft) speed sensor, then go to step 24.






23. 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 B17 and the input shaft (mainshaft) speed sensor, then go to step 24.

NO - Go to step 30.






24. Reconnect all connectors.

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

26. Clear the DTC with the HDS.

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

28. 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 29.


29. 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 28, 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 27.


30. Reconnect all connectors

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

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

33. 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 32. If the PCM was substituted, go to step 1.

NO - Go to step 34.


34. 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 33, 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 32. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 32.