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 (see GENERAL TROUBLESHOOTING INFORMATION ).
- Turn the ignition switch ON (II).
- Clear the DTC with the HDS.
- 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.
- Check under these DATA LIST parameter conditions with the HDS:
- ECT SENSOR above 158°F (70°C)
- IAT SENSOR above 32°F (0°C)
- VSS is 0 mph (0 km/h)
- FSS is CLOSED
- ST FUEL TRIM between 0.69 and 1.47
- Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
- Clear the DTC with the HDS.
- 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.
- 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 TEST ), and also check for damage to the air cleaner element (see AIR CLEANER REMOVAL/INSTALLATION ), 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.
- Replace the throttle body (see THROTTLE BODY REMOVAL/INSTALLATION ).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
- 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.
- Check under these DATA LIST parameter conditions with the HDS:
- ECT SENSOR above 158°F (70°C)
- IAT SENSOR above 32°F (0°C)
- VSS is 0 mph (0 km/h)
- ST FUEL TRIM between 0.69 and 1.47
- FSS is CLOSED
- 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 14 and recheck. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
- NO - Go to step 15.
- Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
- Remove the intake air duct from the throttle body.
- 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 TEST ), and also check for damage to the air cleaner element (see AIR CLEANER REMOVAL/INSTALLATION ), then go to step 10. If there is damage in the throttle bore, go to 9.
- NO - Go to step 26.
- Turn the ignition switch OFF.
- Replace the IAC valve (see THROTTLE BODY DISASSEMBLY/REASSEMBLY ).
- Turn the ignition switch ON (II).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
- 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.
- Check under these DATA LIST parameter conditions with the HDS:
- ECT SENSOR above 158°F (70°C)
- IAT SENSOR above 32°F (0°C)
- VSS is 0 mph (0 km/h)
- FSS is CLOSED
- ST FUEL TRIM between 0.69 and 1.47
- Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
- Recheck with different load conditions (turn on the headlights, blower motor, rear window defogger and/or A/C, changing the gear position, etc.)
- 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 26 and recheck.