DTC Troubleshooting

DTC Troubleshooting: P0506

DTC P0506:

Idle Control System RPM Lower Than Expected

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. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle for 20 seconds or more.

4. Check for these conditions in the DATA LIST with the HDS:

- ECT SENSOR 1 above 158 °F (70 °C)
- IAT SENSOR above 32 °F (0 °C)
- VSS is 0 mph (0 km/h)
- ST FUEL TRIM between 0.73 and 1.47
- FSS is CLOSED

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

Does the HDS indicate FAILED?

YES -

Go to step 6.

NO -

If the HDS indicates PASSED, go to step 15. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step 4 and recheck.

6. Remove the air intake duct from the throttle body.

7. 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 Procedures. Also check for damage at the air cleaner element Service and Repair, then go to step 9. If there is damage in the throttle bore, go to step 8.

NO -

Check the A/C system or the power steering system, then go to step 17.

8. Replace the throttle body Removal and Replacement.

9. Reset the PCM with the HDS.

10. Do the PCM idle learn procedure PCM Idle Learn Procedure.

11. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle for 20 seconds or more.

12. Check for these conditions in the DATA LIST with the HDS:

- ECT SENSOR 1 above 158 °F (70 °C)
- IAT SENSOR above 32 °F (0 °C)
- VSS is 0 mph (0 km/h)
- ST FUEL TRIM between 0.73 and 1.47
- FSS is CLOSED

13. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0506 indicated?

YES -

Go to step 1 and recheck.

NO -

Go to step 14.

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

Does the HDS indicate PASSED?

YES -

Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 13, go to the indicated DTC's troubleshooting.�

NO -

If the HDS indicates FAILED, check the A/C system and/or power steering system, then go to step 1. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step 12.

15. Remove the air intake duct from the throttle body.

16. 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 Procedures. Also check for damage at the air cleaner element Service and Repair, then go to step 9. If there is damage in the throttle bore, go to step 8.

NO -

Go to step 17.

17. Recheck with different load conditions (turn on the headlights, blower motor, rear window defogger and/or A/C, change the gear position, etc.).

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

Does the HDS indicate PASSED?

YES -

Intermittent failure, the system is OK at this time.�

NO -

If the HDS indicates FAILED, check the A/C system and/or power steering system, then go to step 1. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step 12.