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So I'm in the beginning stages of identifying this vehicle. So far, this is what I've found:
iac circuit is ground side switched.
circuit pinout is as follows:
pin #9 orange
pin #12 yellow/black
pin #10 black/blue
According to the wiring diagram, I have 2 solenoids within the circuit, so my question is, I'm going to have 2 separate control wires for this circuit right?
The circuit is a 3 wire connector. I took these measurements yesterday with the connector plugged in:
orange= 2.57v
yellow/black= 12.0 v
black/blue= 12.68v
I thought i had identified this circuit properly, but the voltage reading on the orange wire of 2.57v is throwing me off. key on engine off of course.
the yellow/black wire is the main feed from the fuse. externally powered internally grounded is what I remember Paul mentioning. so my main question is, why am I seeing 2.57v and not 12v?
almost forgot, the wiring diagram indicated the following symbols for this circuit: pin 9 orange (IACV-P)
and pin 10 black/blue 12.68v said IACV-N. What's the meaning of this? thanks techs.
Step #3 in service info says battery voltage is expected key on, engine off, on both control wires. Maybe service info's wrong and computer's ground pulsing this wire at key on? Or maybe there's high resistance on this circuit and your meter is pulling the voltage down to 2.57V. The P and N means positive and negative, whatever the heck that means, it's just two control wires going to the computer. Disconnect the computer, turn key on, what voltage are you getting now on those two control wires?
orange= 2.57v
yellow/black= 12.0 v
black/blue= 12.68v
How do you have more voltage coming out of this iac than you measured going in lol? Voltage spike from collapsing magnetic field maybe? It would be nice to see scope capture to see computer control in action.
I will hook up my old scope to see if I can "see" this waveform. thanks jreardon. by the way, I will check my voltage readings again just to make sure I'm getting battery voltage as you mentioned on both control wires. thanks buddy.
so when i have iac plugged in, i get low readings, 2.23 volts. when I disconnect the pcm, the volts shot up to 12.5v. That's the orange wire by the way. Is it possible that I could have a bad driver on one control side of the sensor and not the other?
thanks Jreardon.
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