HVAC Fan Ridiculousness

[funwithbono]

@funwithbono - looks like you may be right. I sprayed through that vent and the fan didn't attempt to come on by itself. Further, I put the old controller back in and my climate system appears to be working again. I'll wait a few days to make sure, and will likely still replace both the blower motor and blower motor controller, as the latter has some corrosion on it. Regardless, I'll keep all informed as this might have just saved me a couple hundred dollars in parts. Thank you!

That’s great to hear! A couple more options before replacing those parts is a good cleaning with some ACF-50 and then a nice coating of nano-spray. These are always with me. I use this stuff on everything electrical and electronic (especially when corrosion is present) as a first step before replacement. Everything from circuit boards to sensors, brake switches on my bikes, wheel speed sensors…too many things to mention; I even use on my steering wheel controls when they get a little dicey. Supply chain issues might make finding this stuff tough right now.

Lear Chemical Research Corporation

Lear Chemical Research developing and compounding anti corrosion lubricants and greases, ACF-50, Corrosion Block, Corrosion Block Grease, Rust Block, effectively solving corrosion related problems in the Automotive, Aviation, Industrial, Marine, Motorcycle and Recreational industries.

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NP Formula LLC | Best anti corrosion lubricant and electrical insulation coating

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[tradle]

Well, @funwithbono and everyone - it was fun while it lasted. The behavior returned (the sound of someone repeatedly hitting the fan up button and the HVAC fan maxing out) and eventually could not be turned off. I tried blowing air into that little vent, but it had no effect on the behavior. I'm hypothetically thinking that the controller itself is the issue, but it could be any of the climate parts in the chain. I'm going to work backwards (blower motor/controller, climate controller, FCIM) and test after each step. I will keep you informed as I have seen this behavior asked about in so many forums with no answers for a resolution. I am bound and determined to sort this out.

 

[J_C]

Maybe it's just the switch behind the button? Not sure how easy or if possible to replace just that.

 

[tradle]

Maybe it's just the switch behind the button? Not sure how easy or if possible to replace just that.

That unfortunately is the full FCIM replacement from what I've seen. I dunno; something is telling me this may just be the HVAC blower motor controller. If not, it's likely either the FCIM or the climate controller. I doubt everything is bad, but something is forcing bad behavior out of the system.

 

[J_C]

If it's making a system generated sound like the button is being pushed, it's doubtful that it's the controller. A speed controller could short out (a transistor most likely) to result in full fan speed, but that wouldn't make the sound.

As far as replacing the switch, I was talking about using a soldering iron after tearing it apart, if that is non-destructively possible. You'd take it apart, identify the type of switch, and source a compatible replacement at an electronics supply house like Digikey.

I would investigate other components first, but if it comes down to needing a new FCIM anyway, can't hurt to tear apart the old one.

On the other hand if it is designed like the following, might not be so easy, but at least there is related info here:

Climate Fan repeatedly turns all the way up!

Hello, I have a 2012 Edge Limited. Recently the fan setting for the climate control will randomly turn itself up to the highest setting. It seems to NOT be on the touch screen but maybe something with the actual console part.. Any one else hear of this? Any at home ideas before I have to take it ...

www.fordedgeforum.com

One post mentions the possibility of just cutting the trace to that button to disable it. If it comes down to replacing the FCIM you could try that and see if you can live with it... assuming you have another method of increasing blower speed? Then again you might be able to just put a few layers of scotch tape over that area, increase the distance and/or insulate so it doesn't conduct.

Climate Fan repeatedly turns all the way up!

Hello, I have a 2012 Edge Limited. Recently the fan setting for the climate control will randomly turn itself up to the highest setting. It seems to NOT be on the touch screen but maybe something with the actual console part.. Any one else hear of this? Any at home ideas before I have to take it ...

www.fordedgeforum.com

 

[tradle]

If it's making a system generated sound like the button is being pushed, it's doubtful that it's the controller. A speed controller could short out (a transistor most likely) to result in full fan speed, but that wouldn't make the sound.

As far as replacing the switch, I was talking about using a soldering iron after tearing it apart, if that is non-destructively possible. You'd take it apart, identify the type of switch, and source a compatible replacement at an electronics supply house like Digikey.

I would investigate other components first, but if it comes down to needing a new FCIM anyway, can't hurt to tear apart the old one.

On the other hand if it is designed like the following, might not be so easy, but at least there is related info here:

Climate Fan repeatedly turns all the way up!

Hello, I have a 2012 Edge Limited. Recently the fan setting for the climate control will randomly turn itself up to the highest setting. It seems to NOT be on the touch screen but maybe something with the actual console part.. Any one else hear of this? Any at home ideas before I have to take it ...

www.fordedgeforum.com

One post mentions the possibility of just cutting the trace to that button to disable it. If it comes down to replacing the FCIM you could try that and see if you can live with it... assuming you have another method of increasing blower speed? Then again you might be able to just put a few layers of scotch tape over that area, increase the distance and/or insulate so it doesn't conduct.

Climate Fan repeatedly turns all the way up!

Hello, I have a 2012 Edge Limited. Recently the fan setting for the climate control will randomly turn itself up to the highest setting. It seems to NOT be on the touch screen but maybe something with the actual console part.. Any one else hear of this? Any at home ideas before I have to take it ...

www.fordedgeforum.com

Thanks @J_C - you make excellent points. I have read both of those posts in the past couple weeks as I researched the possible cause of the behavior. I genuinely appreciate your help!

 

[funwithbono]

Thanks @J_C - you make excellent points.

Not to sound redundant but did you try lubricating the switch with one of the electrical products sprays I recommended?

 

[tradle]

Not to sound redundant but did you try lubricating the switch with one of the electrical products sprays I recommended?

Not yet. I haven’t taken the FCIM out yet.

 

[funwithbono]

Not yet. I haven’t taken the FCIM out yet.

I was referring to the actual plastic control buttons “pads” on the dash below the nav screen. Thought maybe they might be sticky around and behind the panel. Just a thought! With the ignition shut down, a good spray and wipe with ACF-50 does remarkable things…

 

[tradle]

I was referring to the actual plastic control buttons “pads” on the dash below the nav screen. Thought maybe they might be sticky around and behind the panel. Just a thought! With the ignition shut down, a good spray and wipe with ACF-50 does remarkable things…

My FCIM is the flat panel version. There aren’t raised buttons, but sections of glass that you press.

 

[tradle]

Hi All - Well, here is the latest... I replaced the blower motor, the blower motor controller and the FCIM today. The climate controller I received didn't have the spot for the heated seats, so I reinstalled the original controller. With my first test, though it was a short one, everything appeared to work. We'll see how things go over time. Thank you to all of you for your help!

 

[J_C]

Seems like it would have been good to replace one part at a time to see which was faulty? I mean, then you either don't pay for the other parts, or can keep the good ones as spares if one of the others fails in the future.

I could've told you it wasn't the fan though, that is still the same old school 2 wire, brushed DC fan that's been used for ages. No fault in it, would result in running faster... kinda the opposite. Granted a bad fan (if shorting out) can fry a speed controller, but with the fan bad it still wouldn't run at the normal, full speed.

 

[tradle]

Seems like it would have been good to replace one part at a time to see which was faulty? I mean, then you either don't pay for the other parts, or can keep the good ones as spares if one of the others fails in the future.

I could've told you it wasn't the fan though, that is still the same old school 2 wire, brushed DC fan that's been used for ages. No fault in it, would result in running faster... kinda the opposite. Granted a bad fan (if shorting out) can fry a speed controller, but with the fan bad it still wouldn't run at the normal, full speed.

I considered doing that, @J_C - but when I really dug in, both the blower motor and blower motor controller both had notable signs of wear. The blower motor's nut was rusted and the whole assembly moved a ton worse than I would have thought. I mentioned the corrosion on the controller in a previous post - looking at the old and new parts side by side, it was an easy choice to replace. The FCIM... the trim on that thing crumbled when I took it out. I was being so deliberate with each clip, and that top trim broke in four places. I would have A-B tested it with the "new" one, but now I am living with the replacement. The only item in the chain that remains now is the climate controller, so we'll see what happens. In a longer drive today, the climate worked better than I think it has in quite some time. It was quiet and worked exactly as I would expect.

 

[DragoneEx]

Ok I need help before I have to lose a leg at the dealership. My wife’s 14 limited is possessed. While driving out of no where the heater begins to rise non stop after several attempts it shuts off, only to start all over again blasting the heat. There’s no telling when it will happen but it’s been happening more often. The noise I hear is like something is touching the buttons. I’ve did a hard reset on the radio (Sony soft touch) and disconnected the battery for 2 hours. Still the same issue. Any ideas that can help.
Thank you

 

[peterk9]

Ok I need help before I have to lose a leg at the dealership. My wife’s 14 limited is possessed. While driving out of no where the heater begins to rise non stop after several attempts it shuts off, only to start all over again blasting the heat. There’s no telling when it will happen but it’s been happening more often. The noise I hear is like something is touching the buttons. I’ve did a hard reset on the radio (Sony soft touch) and disconnected the battery for 2 hours. Still the same issue. Any ideas that can help.
Thank you

Welcome to the Forum.
Your thread was merged with this existing one found using the 'Search' feature (upper right).
I believe member tradle had much the same issue.

Peter

 

[peterk9]

........................................... The only item in the chain that remains now is the climate controller, so we'll see what happens. In a longer drive today, the climate worked better than I think it has in quite some time. It was quiet and worked exactly as I would expect.

Any update?

 

[Michael Blackburn]

Ok I need help before I have to lose a leg at the dealership. My wife’s 14 limited is possessed. While driving out of no where the heater begins to rise non stop after several attempts it shuts off, only to start all over again blasting the heat. There’s no telling when it will happen but it’s been happening more often. The noise I hear is like something is touching the buttons. I’ve did a hard reset on the radio (Sony soft touch) and disconnected the battery for 2 hours. Still the same issue. Any ideas that can help.
Thank you

View attachment 428982

Well, from all the historical posts, I'd say it is your FCIM (the flat, touch control panel) that has internal failures. Only way to fix is to replace the panel.
Fritz

 

[DragoneEx]

Well, from all the historical posts, I'd say it is your FCIM (the flat, touch control panel) that has internal failures. Only way to fix is to replace the panel.
Fritz

I was afraid of that

 

[tradle]

I was afraid of that

Hey @DragoneEx - sorry I missed the conversation. I’m now months into the FCIM replacement and haven’t had a single issue. I found mine on eBay. I opted for the non-glass version due to both availability and cost. The replacement is straightforward—I’d just recommend getting a set of trim removal tools to make life easier. Let me know if you get stuck - I probably made mistakes I shouldn’t have, but the end result was good.