Idle Air Control Functional Testing
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 speed changes.
3. If the engine condition will not change, do as follows.
Special Service Tool New Generation Star Tester Connected to Data Link Connector 2:
a. Connect the Special Service Tools New Generation Star (NGS) tester to the data link connector 2.
b. Verify that diagnostic trouble code No. P0505 is not displayed. If code No. P0505 is shown, carry out troubleshooting of the code No. P0505.
c. Select the SIMULATION TEST function on the NGS display.
d. 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 PCM.
- If the idle speed does not change. Replace the IAC valve.
4. Warm up the engine to normal operating temperature and run it at idle.
5. Turn the electrical loads ON and verify that the engine speed is within the specification.
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.