DTC Troubleshooting

DTC Troubleshooting: P0715

DTC P0715: Input Shaft (Mainshaft) Speed Sensor Circuit Malfunction

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Initial Inspection and Diagnostic Overview

1. Start the engine. Hold the engine speed at 3,000 rpm without load (in neutral) until the radiator fan comes on, then let it idle.

2. Test-drive several minutes.

3. Check the M SHAFT SPD in the DATA LIST with the HDS.

Is any vehicle speed indicated?
YES - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the input shaft (mainshaft) speed sensor and the ECM.

NO - Go to step 4.


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

5. Disconnect the input shaft (mainshaft) speed sensor 3P connector.

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

7. Measure the voltage between input shaft (mainshaft) speed sensor 3P connector terminal No. 1 and body ground.

Is there about 5 V?
YES - Go to step 8.

NO - Repair open in the wire between the ECM (C12) and the input shaft (mainshaft) speed sensor, then go to step 18.






8. Measure the voltage between input shaft (mainshaft) speed sensor 3P connector terminal No. 2 and body ground.

Is there about 5 V?
YES - Go to step 9.

NO - Go to step 10.






9. Measure the voltage between input shaft (mainshaft) speed sensor 3P connector terminals No. 1 and No. 3.

Is there about 5 V?
YES - Go to step 16.

NO - Repair open in the wire between the ECM (C16) and the input shaft (mainshaft) speed sensor, then go to step 18.






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

11. Jump the SCS line with the HDS.

12. Disconnect ECM connector B (49P).

13. Check for continuity between ECM connector terminal B37 and body ground.

Is there continuity?
YES - Repair short in the wire between the ECM (B37) and the input shaft (mainshaft) speed sensor, then go to step 18.

NO - Go to step 14.






14. Connect input shaft (mainshaft) speed sensor 3P connector terminal No. 2 to body ground with a jumper wire.






15. Check for continuity between ECM connector terminal B37 and body ground.

Is there continuity?
YES - Go to step 18.

NO - Repair open in the wire between the ECM (B37) and the input shaft (mainshaft) speed sensor, then go to step 18.






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

17. Replace the input shaft (mainshaft) speed sensor. Input Shaft (Mainshaft) Speed Sensor Replacement (M/T)

18. Reconnect all connectors.

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

20. Reset the ECM with the HDS.

21. Do the ECM idle learn procedure. ECM/PCM Idle Learn Procedure

22. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 176 °F (80 °C)

- Transmission in 5th

- Engine speed between 2,000-3,000 rpm

- Drive for several minutes, then decelerate (with the throttle fully closed) for 8 seconds

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

Is DTC P0715 indicated?
YES - Check for poor connections or loose terminals at the input shaft (mainshaft) speed sensor and the ECM, then go to step 1.

NO - Go to step 24.


24. Monitor the OBD STATUS for DTC P0715 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?
YES - Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in step 23, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the input shaft (mainshaft) speed sensor and the ECM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 22.