I.A.C Valve????

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ecosse
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Re: I.A.C Valve????

Post by ecosse » Wed Feb 06, 2013 11:29 pm

whos mitchel ?

thanks for input rob gona try and get on it asap, and just verify and load my wiring checks to pcm if all good i may take the iac to bits :shock:

customer is trying to find the old one he took off

cheers

kp

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Robski
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Re: I.A.C Valve????

Post by Robski » Wed Feb 06, 2013 11:38 pm

Mitchell on demand, our info systems don't seem to be a patch on what they use over the pond.

PS I don't think Tom will be too charmed hosting Derrecks capture here.

ecosse
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Re: I.A.C Valve????

Post by ecosse » Wed Feb 06, 2013 11:49 pm

didn't realise i was doing wrong by posting derecks capture here oops :roll:

found this diag though on a google search :D
Attachments
wrangler 4.0 4 wire.jpg

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Fat Freddy
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Re: I.A.C Valve????

Post by Fat Freddy » Thu Feb 07, 2013 2:09 am

Just had an IAC on a wrangler (TJ) (short on to fuel rail inside conduit, rail had pushed through split).

4 wire. Each pair was always switching so two high and two low. As a thought looking at yours I would thinking Brown/Green channels OK. Blue/Red open circuit somewhere after the IAC.
But as Robski pointed out Amp clamp will tell you.

What is the definition of that P1505?

HTH
FF

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Robski
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Re: I.A.C Valve????

Post by Robski » Thu Feb 07, 2013 8:40 am

Kenny

from the diagram you were given it looks like just a motor so find your pairs & as above !

ecosse
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Re: I.A.C Valve????

Post by ecosse » Thu Feb 07, 2013 9:18 pm

thanks guys will post back ASAP :D

ScannerDanner
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Re: I.A.C Valve????

Post by ScannerDanner » Tue Feb 12, 2013 2:36 am

Here is a known good capture of a Chrysler 4-wire stepper type IAC valve. I have included the jpg picture from my eBook and the original psd files.
I believe you have an open in one of the drivers in the PCM (could be an open in one of the wires too). If my suspicions are correct, when you unplug this IAC you will only see activity on 3 channels. The fourth will be dead.
This may also explain the weird pattern on the beginning part of the one channel. (failing driver)

Also as Robski suggested, a current measurement would tell you the same thing. I believe you will have flow on only two wires.
Attachments
4.psd
IAC unplugged during bi-directional extend and retract mode
(462.6 KiB) Downloaded 248 times
3.psd
IAC plugged in during bi-directional extend and retract mode
(481.51 KiB) Downloaded 247 times
Chrylser Stepper Type IAC.jpg
Last edited by ScannerDanner on Tue Feb 12, 2013 2:59 am, edited 1 time in total.

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Re: I.A.C Valve????

Post by ScannerDanner » Tue Feb 12, 2013 2:54 am

After looking at your file closer. I believe you will find the issue on the red and blue channels (one of those two has a completely open driver or an open control wire). Also the tan channel looks like crap, but it is actually still functional.

ScannerDanner
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Re: I.A.C Valve????

Post by ScannerDanner » Tue Feb 12, 2013 2:57 am

Fat Freddy wrote:Just had an IAC on a wrangler (TJ) (short on to fuel rail inside conduit, rail had pushed through split).

4 wire. Each pair was always switching so two high and two low. As a thought looking at yours I would thinking Brown/Green channels OK. Blue/Red open circuit somewhere after the IAC.
But as Robski pointed out Amp clamp will tell you.

What is the definition of that P1505?

HTH
FF
Oh crap, sorry I didn't read your post before posting my response. I agree with you completely.

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Fat Freddy
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Re: I.A.C Valve????

Post by Fat Freddy » Tue Feb 12, 2013 3:11 am

Oh crap, sorry I didn't read your post before posting my response. I agree with you completely.
:lol: :lol: :lol:
Voltage spikes indicate current flow
Would this only apply where an inductive circuit is operating correctly?
In other words the lack of a spike could indicate poor current flow or a shorted winding? Is that correct?

FF

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