DTC Troubleshooting: P1077 (106)
DTC P1077:
 IMT Valve Stuck in High RPM Position
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
  1. Turn the ignition switch ON (II).
  1. Clear the DTC with the HDS.
  1. Do the IMT TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the IMT actuator and the ECM.■
NO -
Go to Step 4 .
  1. Turn the ignition switch OFF.
  1. Disconnect the IMT actuator 5P connector.
  1. Turn the ignition switch ON (II).
  1. Measure voltage between IMT actuator 5P connector terminal No. 1 and body ground.
Is there about 5 V?
YES -
Go to Step 12 .
NO -
Go to Step 8 .
  1. Turn the ignition switch OFF.
  1. Jump the SCS line with the HDS.
  1. Disconnect ECM connector B (44P).
  1. Check for continuity between IMT actuator 5P connector terminal No. 1 and ECM connector terminal B18.
Is there continuity?
YES -
Go to Step 37 .
NO -
Repair open in the wire between the ECM (B18) and the IMT actuator, then go to Step 31 .
  1. Measure voltage between IMT actuator 5P connector terminal No. 3 and body ground.
Is there about 5 V?
YES -
Go to Step 17 .
NO -
Go to Step 13 .
  1. Turn the ignition switch OFF.
  1. Jump the SCS line with the HDS.
  1. Disconnect ECM connector B (44P).
  1. Check for continuity between IMT actuator 5P connector terminal No. 3 and ECM connector terminal B39.
Is there continuity?
YES -
Go to Step 37 .
NO -
Repair open in the wire between the ECM (B39) and the IMT actuator, then go to Step 31 .
  1. Turn the ignition switch OFF.
  1. Jump the SCS line with the HDS.
  1. Disconnect ECM connector B (44P).
  1. Check for continuity between IMT actuator 5P connector terminal No. 2 and ECM connector terminal B33.
Is there continuity?
YES -
Go to Step 21 .
NO -
Repair open in the wire between the ECM (B33) and the IMT actuator, then go to Step 31 .
  1. 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 IMT actuator, then go to Step 31 .
NO -
Go to Step 22 .
  1. Check for continuity between ECM connector terminal B38 and body ground.
Is there continuity?
YES -
Repair short in the wire between the ECM (B38) and the IMT actuator, then go to Step 31 .
NO -
Go to Step 23 .
  1. Check for continuity between IMT actuator 5P connector terminal No. 4 and ECM connector terminal B37.
Is there continuity?
YES -
Go to Step 24 .
NO -
Repair open in the wire between the ECM (B37) and the IMT actuator, then go to Step 31 .
  1. Check for continuity between IMT actuator 5P connector terminal No. 5 and ECM connector terminal B38.
Is there continuity?
YES -
Go to Step 25 .
NO -
Repair open in the wire between the ECM (B38) and the IMT actuator, then go to Step 31 .
  1. Move the IMT valve by hand.
Does it move smoothly?
YES -
Go to Step 27 .
NO -
  1. Reconnect all connectors and the battery.
  1. Turn the ignition switch ON (II).
  1. Do the IMT TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES -
NO -
Go to Step 38 .
  1. Reconnect all connectors and the battery.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1077 indicated?
YES -
Check for poor connections or loose terminals at the IMT actuator and the ECM, then go to Step 1 .
NO -
Go to Step 36 .
  1. Monitor the OBD STATUS for DTC P1077 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 34 , go to the indicated DTC's troubleshooting.■
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the IMT actuator and the ECM, then go to Step 1 . If the screen indicates NOT COMPLETED, go to Step 34 .
  1. Reconnect all connectors.
  1. Start the engine.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1077 indicated?
YES -
Check for poor connections or loose terminals at the IMT actuator and the ECM. If the ECM was updated, substitute a known-good ECM, then go to Step 39 . If the ECM was substituted, go to Step 1 .
NO -
Go to Step 41 .
  1. Monitor the OBD STATUS for DTC P1077 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. If any other Temporary DTCs or DTCs were indicated in Step 40 , go to the indicated DTC's troubleshooting.■
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the IMT actuator and the ECM. If the ECM was updated, substitute a known-good ECM, then go to Step 39 . If the ECM was substituted, go to Step 1 . If the screen indicates NOT COMPLETED, keep idling until a result comes on.