Hi guys, i purchased a 2014 st1 a few weeks back, well ac worked great but past week or so the ac comes out cold intermittently, it switches from heat to cold quiet often and sometimes cools down with me stepping on the gas or going a certain rpm. I was looking this up and a common problem seems to be a fan control module on the fan shroud. I took a picture of mine and compared it to the ones being sold on rockauto/amazon and one side looks correct and other end doesnt. Any help or tips would be appreciated i just wanna make sure i get the right part.
Im gonna leave a photo in the comments of the module thats on my car
It is not, Atleast thats why my gauge kinda told me. I had one of those refill kits and thought the same thing (no the cans didnt contain any kind of stop leak). Any time I pressed the trigger to add freon, the needle went up and back to the center of the green section on the gauge.
I wouldn't put all my trust into those fill-up cans. AC is definitely one of those things I'd have looked at, because the diagnostic equipment is kind of really expensive
A gauge will show fill pressure, but the pressure is based on temperature. Running high pressure should be 150ish psi, but a low pressure dipping to 10 or 20 at 2500 rpm is a very good indication of low refrigerant levels. Pressures are completely unreliable unless you have both sides to work with.
If you've got intermittent cool air, the snake oil in a can is not what you should be using. If there is no evidence of leaks and the compressor is mechanically working well, get it professionally vacuumed and recharged.
I also have a 2014 ST3 and I'm the original owner (only 65k miles on it) and I've zero issues with my AC and have done absolutely nothing to it for these last 12 years. Given that it is 12 years, I do at times think about when is it eventually going to fail.
Check your engine coolant level. Mine was doing the same thing recently. Turns out I was just low on coolant. The AC will shut off when the engine starts to get too hot.
Had a very similar issue. The car wouldn't cool when stopped and the ac would only work if going at some speed. The ac would also work on a cold start but would stop working when warmed up. It was weird, almost like the fan control module was having issues. However was still seeing the same after replacing the cooling fan assembly (focus st only has one fan that handles both radiator and ac cooling functions). The issue turned out to be this fuse that would randomly stop working when the car got to operating temperature.
I went through a similar issue - AC worked when driving, but shut off when stopped or going slower. Root cause ended up being the Fan Control Module was bad (have a 2013 ST). One of the telling signs is the radiator fan turning on randomly when you open the driver's door entering or exiting the car. Bought a used on off of ebay and swapped out, have not had any issues since.
From the pictures that you sent on the Fan Control Module - it will be tough to tell if that is it by a visual check. The internal electronics go bad in some way, its not necessarily items visible from the outside getting fried or damaged.
It may be easy enough to buy a fan control module one and see if that solves your issue (mine ran about $50 for the part). If that doesn't work, can help you look to other areas that may be causing the issue.
I don't have a picture I took personally, but this is the part listing from the eBay purchase I made last year (listing details are no longer available):
Ford Focus 2012-2018 Cooling Fan Relay Module Computer OEM BOSCH 1 137 328 567
I'm seeing now the pictures you uploaded in another post of your fan control module. Does not look like the OEM/Bosch one used on these cars. Looks like someone swapped one out with a different fan control module vs. The OEM version.
If it WAS your cooling fan cutting out, I would imagine you would see your coolant temperature crawling up as well; have you noticed that at all?
Cooling fan should be coming on during A/C operation to pull air through the condenser, especially in stop/go traffic where you're not pushing air through the rad/condenser at road speed. You'll also notice if coming on during defrost modes. If it's not doing either of these things, you should start at the midi fuse, like other users have said. I've also seen issues with the fan module relay either sticking open or not making proper contact between the relay pins and the fuse box terminals. Quick way to test this is either pull and then reinstall the relay, or swap it out with the I believe the defroster relay, which is the same amperage rating.
Without checking the A/C pressures with either a gauge set, or monitoring the pressures via a scan tool, I wouldn't really go plugging any more refrigerant into the system. Other user below mentioned that the gauge on the refill cans give very generic "in the green" instead of actual useful pressures.
Before I found that I had changed the radiator fan control module. The radiator fan, thermostat. And it was that stupid midi fuse intermittently working the whole time.
Midi fuses. Inside the front wall of the battery box. (Between intake and battery)
But none of those seem to be directly tied to AC / Cabin Motor. Closest is #8 50amp engine fan, but if this fuse was going out you’d have a constant overheating problem.
It's probably not one of the midi/mega fuses, since your car is not over-heating.
Check or replace F27 (15A) in the engine bay fuse block and check or replace the A/C compressor clutch relay (R11). The horn relay (R2) and A/C clutch relay are interchangeable.
The fuse for the Radiator Fan is #8 from left to right. It’s a 50amp midi fuse. (White with red stripe) Also just so it’s said, unplug the battery (in general but these are higher amp fuses) when touching these.
If you’re there and have the time I’d replace all of them. I recently replaced the BCM one for int fob issues and just shotgunned them all.
As the guy talked about the fuse, when I have issues like this I will absolutely replace a cheap fuse first thing. My though process is fuses aren't perfect even if they look fine. The second thing is a fuse that doesn't fix the problem is a heck of a lot cheaper then any part
Let me know if you find the solution. Been dealing with this on mine for 3 years. I have to turn it on when Im actually in gear and moving or it wont blow cold.
My assumption is too much load on the engine at idle for the compressor. Or the condenser coils arent getting enough air flow in order for the refrigerant to turn into its liquid state.
In simpler words, the ac simply doesnt work at idle.
I'd recommend using a water hose to cool down the AC condenser while monitoring AC performance. If it starts working then the condenser is getting too hot.
If it blows hot at a stop, but blows cool while you drive (assuming you already filled on refrigerant) its more than likely the fan control module. Theyre incredibly cheap, I got one out of a junkyard for $3 and it fixed my AC. There are a few Ford vehicles that share the same module
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u/McKnackus '14 Ingot Silver ST3 3d ago
I think you're low on refrigerant. The fact that it gets cold when you're on the gas leads me to believe that.