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.

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.

The link you sent not working...

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).

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.

Good info. Your link for search doesn't work either. Search links must only be usable for those that created the link.

Yuk! Thanks guys.

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

next question was the connector for the IAC melted and or shorted ? and or any of the wires to it ?

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 ?

You are in my area I just seen - I am in Arlington and most likely could fix your problems.

Engine ser# OW652687. Engine runs and will idle. It will code after running a few minutes, or above 3000 rpm. When IAC was replaced, I noticed the far end from the solenoid had come apart. We scanned it with a factory authorized Panasonic laptop. Codes cleared, but then came right back. Tech was unable to step IAC up or down with his laptop. The connector shows no sign of overheating/melting. Info on the possible fuse would be nice. I did find a 5 fuse block on port top fwd, but all seemed good.

Not to sound like a hard azz - granted I post and try to help out up here on OSO but I make it a 100 % point not to offer my services for free to boaters in and around DFW area plus it is totally not fair for my paying boat customers in the area. Sorry about that, I hope you and whomever understand where I am coming from with these statements and the reasons why.

This is my only means of making a living - working on boats professionally. I also look at it as you already paid Bass Pro for their services and still have a problem with your engine, . This is not a dog to anyone or any repair shops in DFW but in our area many marine repair shops really have not touched a 496 and or not that many because their boat lines that they sell never had them installed when new. ie: Glastron, Tahoe, Larson and so on and so on.

If It comes to a point that you and or can not get your engine fixed correctly, you can always bring it in for service to have me check it. Once again sorry that I can not offer much more help up here but will offer my services on a paid basis to work on it in person.

I have posted a ton of info on the 496 up here and some of those post might help if you wanted to research them.

I have all the OEM tools and all the scan tools there is on the market plus sell new OEM parts to hopefully fix your app.

If you need to buy a new PCM 555 check with me before you buy for a possible better price. I have no idea if you really need an PCM 555 especially without testing all components. They are not cheap brand new. Just saying. Thanks