IAC Valve Operation
Remove IAC valve from throttle body. Connect battery positive lead to terminals B1 and B2 of IAC valve. See Fig 1. To close IAC valve pintle, repeatedly ground terminals S1, S2, S3 and S4 in sequence. To open IAC valve pintle, repeatedly ground terminals S4, S3, S2 and S1 in sequence. Replace IAC valve if pintle does not open and close as specified.