DTC Troubleshooting
DTC P0718: Input Shaft (Mainshaft) Speed Sensor Intermittent FailureNOTE:
^ Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.
^ 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 ON (II).
2. Clear the DTC with the HDS.
3. Test-drive the vehicle for several minutes in the D position through all five gears.
4. Monitor the OBD STATUS for P0718 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES - Go to step 5.
NO - 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 screen indicates NOT COMPLETED, go to step 3.
5. Turn the ignition switch OFF.
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 7.
7. Connect the input shaft (mainshaft) speed sensor connector.
8. Test-drive the vehicle for several minutes in the D position through all five gears.
9. Monitor the OBD STATUS for P0718 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES - Go to step 10.
NO - Troubleshooting is complete. If the screen indicates NOT COMPLETED, go to step 8.
10. Turn the ignition switch OFF.
11. Jump the SCS line with the HDS.
12. Disconnect PCM connector D (17P).
13. Disconnect the input shaft (mainshaft) speed sensor connector.
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 D8 and the input shaft (mainshaft) speed sensor, then go to step 21.
NO - Go to step 15.
15. Connect PCM connector D (17P).
16. Turn the ignition switch ON (II).
17. Measure the voltage between input shaft (mainshaft) speed sensor connector terminal No. 2 and body ground.
Is thereabout 5 V?
YES - Replace the input shaft (mainshaft) speed sensor, then go to step 21.
NO - Go to step 18.
18. Turn the ignition switch OFF.
19. Disconnect PCM connector D (17P).
20. Check for continuity between PCM connector terminal D8 and input shaft (mainshaft) speed sensor connector terminal No. 2.
Is there continuity?
YES - Go to step 27.
NO - Repair open in the wire between PCM connector terminal D8 and the input shaft (mainshaft) speed sensor, then go to step 21.
21. Reconnect all connectors.
22. Turn the ignition switch ON (II).
23. Clear the DTC with the HDS.
24. Test-drive the vehicle for several minutes in the D position through all five gears.
25. Check for 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 26.
26. Monitor the OBD STATUS for IP0718 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete. If any other DTCs were indicated in step 25, go to the indicated DTC's troubleshooting.
NO - If the screen 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 screen indicates NOT COMPLETED, go to step 24.
27. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
28. Test-drive the vehicle for several minutes in the D position through all five gears.
29. Check for 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, 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 screen indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other DTCs were indicated in step 29, go to the indicated DTC's troubleshooting.
NO - If the screen 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, then go to step 28. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 28.