| DTC P1078: | IMT Valve Stuck in Low RPM Position |
| 1. | Turn the ignition switch ON (II). |
| 2. | Clear the DTC with the HDS. |
| 3. | Do the IMT TEST in the INSPECTION MENU with the HDS. Is the result OK? YES - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IMT actuator and the ECM/PCM.n NO - Go to 4. |
| 4. | Turn the ignition switch OFF. |
| 5. | Disconnect the IMT actuator 5P connector. |
| 6. | Turn the ignition switch ON (II). |
| 7. | Check the IMT VALVE SW in the DATA LIST with the HDS. Is CLOSE indicated? YES - Go to 12. NO - Go to 8. |
| 8. | Turn the ignition switch OFF. |
| 9. | Jump the SCS line with the HDS. |
| 10. | Disconnect ECM/PCM connector B (44P). |
| 11. | Check for continuity between ECM/PCM connector terminal B39 and body ground.
Is there continuity? YES - Repair short in the wire between the ECM/PCM (B39) and the IMT actuator, then go to 21. NO - Go to 28. |
| 12. | Check for continuity between ECM/PCM connector terminal B37 and body ground.
Is there continuity? YES - Repair short in the wire between the ECM/PCM (B37) and the IMT actuator, then go to 21. NO - Go to 13. |
| 13. | Check for continuity between ECM/PCM connector terminal B38 and body ground.
Is there continuity? YES - Repair short in the wire between the ECM/PCM (B38) and the IMT actuator, then go to 21. NO - Go to 14. |
| 14. | Check for continuity between IMT actuator 5P connector terminal No. 4 and ECM/PCM connector terminal B37.
Is there continuity? YES - Go to 15. NO - Repair open in the wire between the ECM/PCM (B37) and the IMT actuator, then go to 21. |
| 15. | Check for continuity between IMT actuator 5P connector terminal No. 5 and ECM/PCM connector terminal B38.
Is there continuity? YES - Go to 16. NO - Repair open in the wire between the ECM/PCM (B38) and the IMT actuator, then go to 21. |
| 16. | Remove the IMT actuator. |
| 17. | Move the IMT valve by hand. Does it move smoothly? YES - Go to 18. NO - Replace the IMT valve, then go to 21. |
| 18. | Substitute a known-good IMT actuator. |
| 19. | Turn the ignition switch ON (II). |
| 20. | Do the IMT TEST in the INSPECTION MENU with the HDS. Is the result OK? YES - Replace the original IMT actuator, then go to 21. NO - Go to 28. |
| 21. | Reconnect all connectors. |
| 22. | Turn the ignition switch ON (II). |
| 23. | Reset the ECM/PCM with the HDS. |
| 24. | Do the ECM/PCM idle learn procedure. |
| 25. | Do the IMT TEST in the INSPECTION MENU with the HDS. |
| 26. | Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P1078 is indicated, check for poor connections or loose terminals at the IMT actuator and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting. NO - Go to 27. |
| 27. | Monitor the OBD STATUS for DTC P1078 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES - Troubleshooting is complete.n NO - If the screen indicates FAILED, check for poor connections or loose terminals at the IMT actuator and the ECM/PCM, then go to 1. If the screen indicates NOT COMPLETED, go to 24 and recheck. |
| 28. | Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM. |
| 29. | Do the IMT TEST in the INSPECTION MENU with the HDS. |
| 30. | Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P1078 is indicated, check for poor connections or loose terminals at the IMT actuator and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting. NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.n |