I have a 2013 Focus and for 3 years its had 0 issues whatsoever but last night i pulled up outside my house and i got brake bulb out, so i got out and checked them all and all 3 are working perfect so i went inside, woke up this morning to both front windows down (rear aren't electric thankfully) and a car full of water, my car doesn't have the global thingy where you hold a button to open all windows so it can't be that, what would trigger windows to open? if one of them was slightly not closed? just can't trust my car now and have it down drive with heaters on and can't take it out as what if i go shopping and come back and my windows are down again?

Judging by the weird brake light bulb error with no light out followed by windows randomly opening i'm guessing something electrical has gone? i did hear a car alarm too but didn't sound like my horn and couldn't see indicators flashing so i think its unrelated but at this point it might have been lol, not sure what to do as i don't know if this is just one thing happening then another that's related or completely a coincidence, since starting it in morning i have no errors or anything and everything works fine like it should, currently sat down my drive with heaters on to dry it out.

Is there anything that would trigger windows opening? like car alarm going off? the fact the brake bulb came on dash then went off without a bulb actually being out then the windows i'm thinking a fuse or wiring? i unlocked the car by fob in the moment when i should have checked if it was unlocked first as it might have unlocked itself too, gf moved my keys last night but even if she pressed unlock by accident this wouldn't drop the windows and my car doesn't have the feature where you hold a button to drop all windows, couldn't have been someone trying to steal it as my dashcam and everything was still in it and nothing was taken or damaged. 

The most likely problem is water ingress to the Body Control Module (BCM). Brake lights, Windows, Alarm etc. etc. are all controlled by the BCM.

Water ingress is a common problem to the BCM and a common problem on many models which can cause many random faults. Before investigating the of the BCM and its connectors, disconnect the negative battery lead.

Ideally you need to fully remove all the connectors and then remove the BCM so that you can check for signs of water and/or greenish corrosion. Carefully inspect the plugs and sockets for corrosion.

2 hours ago, unofix said:

The most likely problem is water ingress to the Body Control Module (BCM). Brake lights, Windows, Alarm etc. etc. are all controlled by the BCM.

Water ingress is a common problem to the BCM is a common problem on many models and can cause many random faults. Before investigating the of the BCM and its connectors, disconnect the negative battery lead.

Ideally you need to fully remove all the connectors and then remove the BCM so that you can check for signs of water and/or greenish corrosion. Carefully inspect the plugs and sockets for corrosion.

BCM is located under the glovebox right? how could water get into it though? was raining driving home, so a faulty BCM would also cause the windows to randomly go down too etc? it hasn't done it since but i'm guessing its dried out or something, just been on the phone to a garage and they first said maybe i pressed buttons accidently on the fob which a 2013 Focus doesn't have right where you hold a button and windows go down? but then suggested the BCM but i have it booked in for morning to be checked over as i'm lucky really as anywhere else my dashcam would have been nicked lol.

BCM was tested and turned out to be fine, scanner found codes for rear fog and brake light so those bulbs were changed and so far it hasn't done it since, apparently this garage had a Fiesta in a few months ago where a faulty bulb caused the alarm to go off all the time and windows to open by themselves, i took both lights off and cleaned it all and taped up the wires and changed the bulb so fingers crossed this has fixed it, who knew a bulb going/faulty would cause such weird issues especially allowing windows to drop by themselves, windows should cut power when the car is off completely as this is a massive security floor when you could be parked anywhere and your windows go down...only 2 of mine are electric but if all 4 was then all 4 would have dropped.

If the problem comes back the garage is going to take a look at the wiring and worse case replace the BCM as they don't know what else could be triggering windows to open, safe to say i don't trust my car now and have had to take all my dash cam etc out of it.

I remain yet to be convinced that any faulty lamp would cause the windows to open. My money is still on a problem with the BCM, but time will tell either way.

The garage should know that cars with manual rear windows do not have global opening/closing windows, it's not even an option.

Check for water/corrosion in the door modules, behind the door casings

You have my sympathy. I recently sold my 2013 Focus and feel that I was lucky to have had it for 8 yrs and never had any BCM problems.

Ironic that you've had to take your dashcam out of the car, having installed it to stop people nicking things out of your car! 

 

6 hours ago, unofix said:

I remain yet to be convinced that any faulty lamp would cause the windows to open. My money is still on a problem with the BCM, but time will tell either way.

The garage should know that cars with manual rear windows do not have global opening/closing windows, it's not even an option.

From what i have witnessed personally bulbs can be a pain in the backside, sisters car had the wrong bulb put in by Halfords and her alarm kept going off and stopped once the bulb got changed which you would assume all it would do is put a warning on the dash or simply not work but instead displayed warnings for other bulbs and set the alarm off constantly, garage i took my car to has had loads of cases where bulbs have caused issues and i don't think they'd lie as if anything they would tell me no you need a new BCM etc, car hasn't done anything since and they apparently inspected and tested the BCM and it performed fine, since it happened i am constantly worried and checking my windows but want to make sure the issue is actually sorted before selling it but if it does happen again i suppose a new BCM is the next step as i'm not sure what else could be causing it and they mentioned the global feature before knowing my car was 2013 with rear winders instead of full electrics. 

 

5 hours ago, alanfp said:

You have my sympathy. I recently sold my 2013 Focus and feel that I was lucky to have had it for 8 yrs and never had any BCM problems.

Ironic that you've had to take your dashcam out of the car, having installed it to stop people nicking things out of your car! 

 

Honestly, my car has been great for the 3 years i have had it, only had to replace boot struts and badges on it and the usual wipers etc and just trying to do small jobs to fix previous owners neglect, powershift box was a issue when i bought it though but Evans Halshaw changed the clutch pack and its been fine since, i installed a dashcam due to so many people who just hit your car and drive off especially in car parks but since this happened i have removed it just in case i go into a shop and my windows drop randomly 🤣i'm just paranoid now because it could happen randomly again if the fix doesn't work and with all the rain we're getting its a nightmare but i wouldn't sell it until i knew 100% the windows won't drop but i want a new car anyway as i fancy a 1 series.  

On 1/22/2024 at 1:33 PM, unofix said:

I remain yet to be convinced that any faulty lamp would cause the windows to open. My money is still on a problem with the BCM, but time will tell either way.

The garage should know that cars with manual rear windows do not have global opening/closing windows, it's not even an option.

You was correct lol, only a short term fix it seems as its back doing it now! i ended up taking it to another garage today and they found spots of water on the left side in the boot near all the wiring but couldn't identify the leak, so seems they'll have to find where its coming from and seal it then replace the BCM and code the keys etc, massive issue with Fords and water leaks it seems.

Weird part is the brake lights all work now and no longer showing a message but the windows have started dropping again and the alarm sounding, so in the boot there is another BCM? they said they'll replace the BCM but i thought that was under the glovebox but where the water has been spotted is on all the wiring in the boot on left side.

There is only one Body Control Module (BCM) and it is part of the passenger compartment fusebox. The water in the boot will have nothing to do with the problems with the windows, the only thing it might  have anything to do with is the alarm, but even then i doubt it.

 

There is a small fusebox in the rear of the Mk3 Focus.  I don't think it's a 'smart' GEM, but damp & corrosion there could still be causing a short.

Yeah at this point i am so confused...had enough so i decided i would strip the back of the car and did find a few spots of water so i spent a good few hours tipping water on the car and not a spot entered, today i cleaned it with the jetwash and again bone dry, i was told by a garage to just spray i think its called contact cleaner on the wiring in boot and tape it all so i did and replaced the brake bulb again and it hasn't done anything since...windows are no longer dropping, water leak has somehow vanished and the alarm no longer goes off and all my brake lights work and no warnings on dash, very very confusing to be honest its been driving me nuts, i also had this garage check the BCM and they said its fine too so i doubled down and they basically said we can replace it for you but it would be a waste of your money so i didn't.

So yeah somehow the car has fixed itself...no idea what caused the windows to drop but it hasn't done it since and everything is working perfectly again, maybe the wiring in the boot was damp causing a short like Tom mentioned? either way i can't get the car to leak whatsoever and everything works and i have drove it in the rain again and its been fine but will continue to check on it just to make sure it really is fine but i am just as confused as everyone else.