P0506

DTC P0506: Idle Control System RPM Lower Than Expected

NOTE:
- If DTC P0511 is stored at the same time as DTC P0506, troubleshoot DTC P0511 first, then recheck for DTC P0506.
- 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).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
4. Check under these DATA LIST parameter conditions with the HDS:
- ECT SENSOR above 158 degree F (70 degree C)
- IAT SENSOR above 32 degree F (0 degree C)
- VSS is 0 mph (0 km/h)
- FSS is CLOSED
- ST FUEL TRIM between 0.69 and 1.47

5. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.

Does the screen indicate FAILED?

YES - Go to step 6.

NO - If the screen indicates PASSED, go to step 16. If it is EXECUTING, keep the engine idling until a result comes on. If the screen indicates OUT OF CONDITION, recheck with a different load condition (electrical, A/C, gear position, etc.), then go to step 3.

6. Clear the DTC with the HDS.
7. Do the IACV TEST in the INSPECTION MENU with the HDS.

Is the result OK?

YES - Go to step 8.

NO - Go to step 18.

8. Check for dirt, carbon, or damage in the throttle bore.

Is there dirt, carbon, or damage in the throttle bore?

YES - If there is dirt or carbon, clean the throttle body, and also check for damage to the air cleaner element, then go to step 10. If there is damage in the throttle bore, go to step 9.

NO - Check the A/C system or power steering system, then go to step 26.

9. Replace the throttle body.
10. Reset the ECM/PCM with the HDS.
11. Do the ECM/PCM idle learn procedure.
12. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
13. Check under these DATA LIST parameter conditions with the HDS:
- ECT SENSOR above 158 degree F (70 degree C)
- IAT SENSOR above 32 degree F (0 degree C)
- VSS is 0 mph (0 km/h)
- ST FUEL TRIM between 0.69 and 1.47
- FSS is CLOSED

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

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P0506 is indicated, go to step 1 and recheck. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 15.

15. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates EXECUTING, let the engine idle until a result comes on. If the screen indicates OUT OF CONDITION, go to step 13 and recheck.

16. Remove the intake air duct from the throttle body.
17. Check for dirt, carbon, or damage in the throttle bore.

Is there dirt, carbon, or damage in the throttle bore?

YES - If there is dirt or carbon, clean the throttle body, and also check for damage to the air cleaner element, then go to step 10. If there is damage in the throttle bore, go to step 9.

NO - Go to step 26.

18. Turn the ignition switch OFF.
19. Replace the IAC valve.
20. Turn the ignition switch ON (II).
21. Reset the ECM/PCM with the HDS.
22. Do the ECM/PCM idle learn procedure.
23. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
24. Check under these DATA LIST parameter conditions with the HDS:
- ECT SENSOR above 158 degree F (70 degree C)
- IAT SENSOR above 32 degree F (0 degree C)
- VSS is 0 mph (0 km/h)
- FSS is CLOSED
- ST FUEL TRIM between 0.69 and 1.47

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

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P0506 is indicated, check for poor connections or loose terminals at the IAC valve and the ECM/PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 27.

26. Recheck with different load conditions (turn on the headlights, blower motor, rear window defogger and/or A/C, changing the gear position, etc.)
27. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the IAC valve and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING, keep the engine idling until a result comes on. If the screen indicates OUT OF CONDITION, go to step 26 and recheck.