DTC P0506: Idle Control System RPM Lower Than Expected
- Turn the ignition switch to ON (II).
- Clear the DTC with the HDS.
- Start the engine. Hold the engine speed at 3, 000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle.
- Check under these DATA LIST parameters with the HDS:
- ECT SENSOR 1 above 156°F (70°C)
- IAT SENSOR above 32°F (0°C)
- VSS is 0 mph (0 km/h)
- ST FUEL TRIM between 0.69-1.47
- FSS is CLOSED
- 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 15. If the screen indicates EXECUTING, keep idling until a result comes on. If the screen indicates OUT OF CONDITION or NOT COMPLETED, go to step 4 and recheck.
- Remove the air cleaner (see AIR CLEANER REMOVAL/INSTALLATION ).
- 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 (see THROTTLE BODY CLEANING ). Also check for damage to the air cleaner element (see AIR CLEANER ELEMENT INSPECTION/REPLACEMENT ), then go to step 9. If there is damage in the throttle bore, go to step 8.
NO: Check the A/C system and the power steering system, then go to step 9.
- Replace the throttle body (see THROTTLE BODY REMOVAL/INSTALLATION ).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM IDLE LEARN PROCEDURE .
- Start the engine. Hold the engine speed at 3, 000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle.
- Check under these DATA LIST parameters with the HDS:
- ECT SENSOR 1 above 156°F (70°C)
- IAT SENSOR above 32°F (0°C)
- VSS is 0 mph (0 km/h)
- ST FUEL TRIM between 0.69-1.47
- FSS is CLOSED
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0506 indicated?
YES: Check the A/C system and/or the power steering system, then go to step 1
NO: Go to step 14.
- Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.
Does the screen 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 the 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 11 and recheck.
- Remove the air cleaner (see AIR CLEANER REMOVAL/INSTALLATION ).
- 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 (see THROTTLE BODY CLEANING ). Also check for damage to the air cleaner element (see AIR CLEANER ELEMENT INSPECTION/REPLACEMENT ), then go to step 9. If there is damage in the throttle bore, go to step 8.
NO: Go to step 17.
- Recheck with different load conditions (turn on the headlights, the blower motor, the rear window defogger, the A/C, and/or the power steering system, change the gear position, etc.).
- Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.
Does the screen 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 the power steering system, then go to step 1 and recheck. 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 17.
- Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ).