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496 HO- No IAC voltage

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Old 02-21-2016, 12:01 PM
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Default 496 HO- No IAC voltage

I have 2007 496 HO with manual controls. It started beeping codes at the end of last season. I replaced the MAP sensor and the IAC with filter due to their age.
I'm still getting codes, so I took it to the local Bass Pro for ECM scan. It had many hits for the IAC valve. We also tried to control the IAC stepping via the laptop.
We got no response. I'm checking for voltage on the IAC wires and get none with IGN on but no cranking. I do not see any wiring damage on harness at either end.
Has anyone ever experienced something like this before. I'm new to this forum and would appreciate any help. Thanks.
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Old 02-21-2016, 12:27 PM
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Here's a quick search, you may want to refine, as 496's have common IAC issues:
http://www.offshoreonly.com/forums/s...archid=3050251

That said, a member BUP has helped diagnose many of these problems and hopefully will come by this thread soon.
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Old 02-21-2016, 12:34 PM
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The link you sent not working...
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Old 02-21-2016, 12:39 PM
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You likely found this site via Google. Now, try this site's search function which works pretty well.

That said, I suspect the driver in your PCM for the IAC is fried.

Use search term "IAC driver", which is what this search is:
http://www.offshoreonly.com/forums/s...archid=3050281

You can buy a new PCM, or you can send it off to Dustin at Whipple, who can reprogram it (likely the cheaper option).
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Old 02-21-2016, 12:42 PM
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Hmmm.nout sure why, but anyway...top right hand corner of each page you'll see a rectangle fill in box that says 'search here....'

Just enter IAC, click the small symbol just to the right of it that looks like a magnifying glass, and since the 496 has the most IAC problems by volume, you'll see alot of these threads come up under even that basic search.
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Old 02-21-2016, 12:43 PM
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Good info. Your link for search doesn't work either. Search links must only be usable for those that created the link.

Quote:
Originally Posted by Sydwayz View Post
You likely found this site via Google. Now, try this site's search function which works pretty well.

That said, I suspect the driver in your PCM for the IAC is fried.

Use search term "IAC driver", which is what this search is:
http://www.offshoreonly.com/forums/s...archid=3050281

You can buy a new PCM, or you can send it off to Dustin at Whipple, who can reprogram it (likely the cheaper option).
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Old 02-21-2016, 12:55 PM
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Yuk! Thanks guys.
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Old 02-21-2016, 04:04 PM
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How hard is your engine to start does it start right up ? does your engine stay running and or throttle up like it should ? condition of the how the engine is running ? No voltage at all to IAC can be Bad fuse is where I would start first then move on to the other areas.

you need to post your engine serial # and I can lead you to where that is to see if that is a possible problem.

easy things first to rule out or to find the problem and move on from there to the more expensive parts

Last edited by BUP; 02-21-2016 at 04:33 PM.
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Old 02-21-2016, 04:09 PM
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next question was the connector for the IAC melted and or shorted ? and or any of the wires to it ?
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Old 02-21-2016, 04:17 PM
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next was the connector replaced with IAC - the connector 25 % of the time can be a problem as well.

Was the IAC faults cleared and cleared out of the history after new parts installed and then rescaned ?

what scan tool was used ?

Last edited by BUP; 02-21-2016 at 04:27 PM.
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