Code 35, Idle Speed Error: Notes

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Code 35 will set when closed throttle engine speed is 150 RPM greater or less than correct idle speed for 20 seconds.

NOTE: Test numbers refer to test numbers on diagnostic chart.

IAC driver is used to extend and retract IAC valve. Movement is verified by changing engine speed. If no engine speed change occurs, valve can be retested when removed from throttle body.
Checks IAC movement quality from step 1). Between 700-1500 RPM, engine speed should change smoothly with each tester light flash while extending or retracting. If IAC valve is retracted beyond control range (about 1500 RPM), it may take many flashes in extend position before engine speed reduces. This is normal on some engines. Fully extending IAC may cause engine to stall. This may be normal.
Steps 1) and 2) verified proper IAC valve operation. This step checks IAC circuits. Each light on node light should flash Red and Green, while IAC valve is cycled. While color sequence is not important, if either light is off or does not flash Red and Green, check circuits beginning with poor terminal contacts.