P0506
DTC P0506 IDLE AIR CONTROL SYSTEM-RPM LOWER THAN EXPECTEDComponent Location:
GENERAL DESCRIPTION
When the TP sensor's signal indicates closed throttle position and the engine is idling, the PCM adjusts the idle speed control actuator so that the engine runs at the correct idling speed, regardless of coolant temperature, load and etc. When the additional load applied in the engine, the air flow through the idle speed control actuator is increased momentarily to raise the idling speed.
DTC DESCRIPTION
The PCM monitors engine speed deviation from the target idle engine speed when the vehicle is stopped and the idle speed valve opening is stable. The PCM sets DTC P0506 if the difference to the target idle engine speed is lower than the predetermined threshold.
DTC Detecting Condition:
Specification:
Schematic Diagram:
Signal Waveform:
MONITOR DTC STATUS
NOTE: If any TPS, MAFS or ISCA Valve circuit codes are present, do ALL REPAIRS associated with them before proceeding with this troubleshooting tree.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F4(DTAL) to select DTC information from the DTCs menu
3. Confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Read "DTC Status" parameter
5. Is parameter displayed "History(Not Present) fault"?
NOTE:
1. History (Not Present) fault: DTC occurred but has been cleared.
2. Present fault: DTC is occurring at present time.
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for loose or poor connections, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "Check for restricted intake or exhaust system" procedure.
CHECK FOR RESTRICTED INTAKE OR EXHAUST SYSTEM
1. Visually/physically inspect the following items:
- Air cleaner filter element for excessive dirt or for any foreign objects
- Throttle body inlet for damage or for any foreign objects
- Restricted exhaust system
2. Was a problem found in any of the above areas?
YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "W/harness Inspection" procedure.
TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO: Go to next step as below.
COMPONENT INSPECTION
1. Ignition "OFF".
2. Remove ISCA Valve from Throttle body. Check for throttle bore, throttle plate and the ISCA passages for chocking and for any foreign objects. Repair or clean as necessary.
3. Install the ISCA valve.
4. Ignition "ON" & Engine "OFF".
5. Install scan tool and select "IDLE SPEED ACTUATOR" parameter on the "Actuation Test" mode.
6. Activates ISCA valve by pressing "STAT" key.
7. Check the ISCA valve for clicking sound and visually verifying valve closes and opens.
NOTE: Repeat numerous times to ensure valve reliability
8. Is ISCA Valve OK?
YES: Check for poor connection between PCM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Check ISCA for contamination, deterioration, or damage. Substitute with a known-good ISCA and check for proper operation. If the problem is corrected, replace ISCA and then go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode
2. Press F4(DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter
4. Is parameter displayed "History(Not Present) fault"?
YES: System performing to specification at this time. Clear the DTC
NO: Go to the applicable troubleshooting procedure.