Idle Air Control (IAC) Inspection
IDLE AIR CONTROL INSPECTION1. Start the engine and run it at idle.
2. Disconnect the idle air control (IAC) valve connector and verify that the engine rotation changes.
3. If the engine condition will not change, proceed as follows:
- Connect the SSTs (NGS) to the data link connector 2 located under the driver side dashboard.
- Verify that diagnostic trouble code No. PO505 is not displayed.
- If code No. P0505 is shown, carry out troubleshooting of the code No. P0505.
- Select the "SIMULATION TEST" function on the NGS display.
- Change the duty value of the IAC valve to 100% by using the "IACV" and verify that the idle speed increases.
- If the idle speed increases, replace the ECM.
- If the idle speed does not change, replace the BAC valve.
4. Warm up the engine to normal operating temperature and run it at idle.
5. Turn the electrical loads ON and verify that engine speed is maintained within the specified range(s).
Idle Specifications:
NOTE: Excludes temporary idle speed drop just after the electrical loads are turned on.
6. If not as specified, check the related switches and wiring harnesses.