The circuit for the IACV is here for the two pins valve:
Some basic testing for that:
1. Square iagnstic port 3 and connector 1 at the valve: check for continuity voltmeter positive to pin 2 of the valve coupling and ground, ignition on, 11-14 volts reading. (if not, check or OVP contact 1 is voltage fed at all times, OVP fuse blown, corroded posts, or OVP contact 6/terminal 15 or OVP contact 2/terminal 87 or OVP contact 5/terminal 31 for open circuits)
2. Ignition off, at the boxed diagnostic port check resistance between 3 (minus) and 4 (plus), 20-30 ohms correct range.
3. Checkfor the valve to click if disconnected and apply minus at 1 and plus at 2
4. Square diagnostic port 3 and connector 1 at the valve: check for continuity with the multimeter in ohmmeter mode
5. Square diagnostic port 4 and connector 2 at the valve: check for continuity
6. place voltmeter minus at square diagnostic port 20 and plus at the positive battery post, you should read 11-14 volts or you have no ground
7. Engine at idle, voltmeter on pin 25 at the diagn and minus at the negative battery post. In Park you should have 11-14 volts, secure vehicle with parking brake and in drive voltage should drop (if not neutral switch has gremlins).
8. Check the AC cut signal (engine at idle, AC on) at diag port with a voltmeter with minus at port 2 and plus at port 19... you should have there 11-14 volts or either check further the AC compressor control module (N6) or cable@ pressure switch compressor cutoff (S3 1)
9. Good lucko!
