With Integrated Fault-Diagnosis System (Flash Codes): 12222

Diagnostic procedure, LH 2.4.2

For fault diagnosis, see also "Checking the idle air control valve". Testing and Inspection




1 Of the LH tester has been used, go to point 2.

With the ignition switch in the Drive position, select command code 553 on the ISAT scan tool or carry out component testing with the self-diagnostics function.

Check by listening for the sound of the idle air control valve working (1 Hz).

2 With the ignition switch in the Drive position, check that battery voltage is present across pin 2 of the IAC valve connector and a good ground. If it is not, check the lead between pin 2 of the IAC valve and pin 87 of the main relay for continuity/shorting and the operation of the relay.

3 Connect test LED 86 11 857. Ignition switch in the ON position. One lead to the battery positive terminal and one lead to pin 1 and pin 3 of the IAC valve connector. The LED should light up in both cases.

If it does not, go to point 5.

If it does, go to point 4.




4 With the ignition switch in the OFF position and the IAC valve connector unplugged, check the. Resistance of the valve's two motor windings across-pins 1 and 2 and across pins 2 and 3. The resistance should be 10 - 15 ohms in each winding.

If it is not, change the IAC valve.

5 Plug the Breakout Box into the car's wiring harness (LH control module not connected). Check the lead between pin 33 of the LH control module and pin 1 of the IAC valve, as well as the lead between pin 15 of the control module and pin 3 of the IAC valve, for continuity/shorting.

6 Try fitting a new LH control module.

Important: Do not touch the slide with a hard object such as a screwdriver as this could scratch it and cause the valve to bind.