P1078
DTC P1078: Intake Manifold Runner Control Valve Stuck Long1. Turn the ignition switch ON (II).
NOTE: Do not start the engine.
2. Clear the DTC with the HDS.
3. Make sure the IMRC SOL is ON in the DATA LIST with the HDS.
4. Check the IMRC VLV SW in the DATA LIST with the HDS.
Is OPEN indicated?
YES - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the intake manifold runner control actuator and PCM.
NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Disconnect the intake manifold runner control actuator 5P connector.
7. Turn the ignition switch ON (II).
8. Measure voltage between intake manifold runner control actuator connector terminal No.3 and body ground.
Is there about 5 V?
YES - Go to step 9.
NO - Go to step 13.
9. Turn the ignition switch OFF.
10. Jump the SCS line with the HDS.
11. Disconnect PCM connector A (73P).
12. Check for continuity between PCM connector terminal A28 and intake manifold runner control actuator connector terminal No.2.
Is there continuity?
YES - Go to step 17.
NO - Repair open in the wire between the intake manifold runner control actuator and the PCM (A28), then go to step 23.
13. Turn the ignition switch OFF.
14. Jump the SCS line with the HDS.
15. Disconnect PCM connector A (73P).
16. Check for continuity between PCM connector terminal A41 and intake manifold runner control actuator connector terminal No.3.
Is there continuity?
YES - Go to step 27.
NO - Repair open in the wire between the PCM (A41) and intake manifold runner control actuator, then go to step 23.
17. Check for continuity between PCM connector terminal A9 and intake manifold runner control actuator connector terminal No.5.
Is there continuity?
YES - Go to step 18.
NO - Repair open in the wire between the PCM (A9) and intake manifold runner control actuator, then go to step 23.
18. Check for continuity between PCM connector terminal A9 and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (A9) and the intake manifold runner control actuator, then go to step 23.
NO - Go to step 19.
19. Check for continuity between PCM connector terminal A10and intake manifold runner control actuator connector terminal No.4.
Is there continuity?
YES - Go to step 20.
NO - Repair open in the wire between the PCM (A10) and intake manifold runner control actuator, then go to step 23.
20. Check for continuity between PCM connector terminal A10 and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (A10) and the intake manifold runner control actuator, then go to step 23.
NO - Go to step 21.
21. Remove the intake manifold runner control actuator.
22. Move the intake manifold runner control valve by hand.
Does it move smoothly?
YES - Replace the intake manifold runner control actuator, then go to step 23.
NO - Remove the intake manifold upper cover and repair the stuck valve. If necessary, replace the intake manifold, then go to step 23.
23. Turn the ignition switch ON (II).
24. Reset the PCM with the HDS.
25. Do the PCM idle learn procedure.
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 intake manifold runner control actuator and PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - Troubleshooting is complete.
27. Update the PCM if it does not have the latest software or substitute a known-good PCM.
28. Do the PCM idle learn procedure.
29. 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 intake manifold runner control actuator and PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.