Alarm keeps going off - Ive had to disconnect battery!

[cokey]

The alarm on my 03 MCS has gone off virtually non-stop today, while I was at work (much to the annoyance of several colleagues). It's gotten so bad that I've had to disconnect the battery tonight, when I got home.

Here's a run down of what I looked at to try and troubleshoot: I tried opening/closing all doors and boot. No warning lights were on to suggest boot or bonnet open. I disabled the motion and tilit sensors (double press of fob button). This made no difference, alarm still going nuts every few minutes.

I ended up having to leave it unlocked so the alarm was off. When I left to go home, I noticed that the interior lights were on when I approached the car. They also started coming on while driving - at times they were flickering on and off. I had to disable them in the end (holding the light switch for a few seconds until it flashed).

The alarm problem continued at home. At one point I left the car unlocked for about 4 mins, with the doors shut. The interior lights stayed on (I had enabled them again) but when I touched the door handle (from the outside) they immediately went off again. I didnt actually open the door, just touched the handle very lightly. I'm thinking that there must be a faulty switch somewhere in the door, or handle. This faulty switch is activating for no apparent reason, and the car is thinking that the door is being tampered with, turning on the interior lights and the alarm.

Can anyone share any info about this problem? Does my diagnosis sound correct? Where exactly is the switch that I need to look at/replace?

Is there any way of actually disabling the alarm until I have fixed the problem?

Thanks in advance for any advice

[Snowie]

Sounds like a faulty door lock - have heard of weird alarm traights due to this.

If you use the key in the door lock will the car lock without the alarm sounding??

[S8RAH]

Ooo, long time since this happened to me (6 years to be exact).
It was a problem with the sensor or switch in the door which closes the window that last little bit when you shut the door. I can't remember if it didn't close the window or didn't recognise that it was closed but replacing it fixed the problem. Oddly, the MINI down the road did exactly the same thing a week later.
Hope this helps.

[cokey]

Quote: Originally Posted by Snowie (original)

Sounds like a faulty door lock - have heard of weird alarm traights due to this.

If you use the key in the door lock will the car lock without the alarm sounding??

Thanks for the reply Snowie. The car is actually at the local tyre fitters as I've had a problem with a new runflat tyre they fitted...another story. I'll try the key in the door lock to see if it enables the alarm or not. Hopefully it doesn't - that would give me a bit of breathing space to find the fault, without having to disconnect the battery each night. When the interior light goes on and off randomly, the locks aren't actually doing anything. I really need to try and research/understand what switches are in the door.

EDIT: Just tried the key in lock but it turns on alarm. Looks like I'm going to have to continue to disconnect battery at night, until I've figured out and fixed this problem.

Quote: Originally Posted by S8RAH (original)

Ooo, long time since this happened to me (6 years to be exact).
It was a problem with the sensor or switch in the door which closes the window that last little bit when you shut the door. I can't remember if it didn't close the window or didn't recognise that it was closed but replacing it fixed the problem. Oddly, the MINI down the road did exactly the same thing a week later.
Hope this helps.

Thank you too S8rah for your reply. Do you remember if your interior light was turning on and off randomly? I suspect that my problem is to do with a different switch than the window one, because of the interior light.

[Snowie]

In some cases the windows get a mind of their own and roll down slightly as if you are opening the door.

[cokey]

Quote: Originally Posted by Snowie (original)

In some cases the windows get a mind of their own and roll down slightly as if you are opening the door.

Yeah, that makes sense. I haven't noticed the windows doing that while the interior light is going on and off, but i will certainly look out for it later, when i've got the car back again.

[jango-fett]

the problem is probably with the microswitch in the door latch that acts as a door ajar switch. ( i would expect to see the windows going down then up as the light comes on and off)

Therefore there wont be any issues with locking and unlocking, just the status of whether your door is open or shut, hence bringing your light on and setting of the alarm.

There could be a couple of reasons for this....
1) BC1 - there were problems with the bc1 and water ingress........
2) Water in the door connector to body harness connection in the apost
3) water ingress into the door latch

Its worth doing a continuity check across the door ajar switch, at the apost harness connector...
Then you can see if the connector is ok and eliminate the door latch at the same time..
good luck.

[cokey]

Quote: Originally Posted by jango-fett (original)

the problem is probably with the microswitch in the door latch that acts as a door ajar switch. ( i would expect to see the windows going down then up as the light comes on and off)

Therefore there wont be any issues with locking and unlocking, just the status of whether your door is open or shut, hence bringing your light on and setting of the alarm.

There could be a couple of reasons for this....
1) BC1 - there were problems with the bc1 and water ingress........
2) Water in the door connector to body harness connection in the apost
3) water ingress into the door latch

Its worth doing a continuity check across the door ajar switch, at the apost harness connector...
Then you can see if the connector is ok and eliminate the door latch at the same time..
good luck.

Thanks Jango, for the reply.

Could I be so bold as to ask for a little more detail on how to check for continuity? I hava a multimeter and know how to use it but exactly where should I be putting the probes etc?

The problem hasn't actually happened at all today. No false alarms and no interior lights going on and off so I havent been able to look out for the windows doing that little drop.

I'm still going to disconect battery tonight, as I'm not confident that the alarm won't go off and wake all the stroppy neighbours up.

[cokey]

OK, well the problem hasn't come back now and it's been over a week.

The only thing I did was reset the drivers window (open full and hold switch down for 15 secs). It's probably just coincidence that the problem has gone after I did this, and I wouldn't be surprised if it resurfaces one day soon (or middle of night, knowing my luck).

One thing I will do, as soon as I get the chance, is check the BC1 for wet/damp etc.

I'll repost here if anything more happens with the problem

[S8RAH]

It was -6 C when mine failed and the neighbours failed at a similar temperature, it could be that the switch just gets cold, bless it

[cokey]

OK, alarm problem back again - went off at 11pm last night.

When I went out to check, I noticed the passenger window doing the up down thing, going crazy. Reason I hadn't seen this before, is that the passenger window was not working at the time of the first round of alarms. I fixed it last week with the 'bang, bang, bang' method.

Seems highly likley now, that the problem is the switch in the door latch. I'm going to source a new one and replace over the weekend. I'll do a write up with photos for anybody that might need it in future.

[DrNorman]

A write up would be excellent!

Hope it goes ok and not too fiddly!

[cokey]

OK, I've changed the rotary lock latch. Easy job but was quite fiddly and at times excrutiatingly frustrating. Took me hour and a half - should have only take an hour but I had to take the thing out again, after securing everything in place, as it was impossible to get a cable reattached - will explain when I do the write up. If i had to do the job again, I reckon I could do it in a half hour.

I've taken a few pics and will do a detailed 'how to' in the next couple of days or so. The 'how to' will make it simple for anybody to do this job and will also help you skip all the frustration I had when doing it, as I've found the perfect method now.

Lets hope that the latch really was the cause of my problems and not the BC1. I'll report backshortly.

[lowercasemark]

Guys, I'm having the exact same problem at the minute, and it's driving me nuts... every time I hear an alarm I make a dash for my car keys! Seems to be triggered by cold weather too (no problems when temp is above freezing), and I've resorted to leaving the car unlocked at night to get some sleep - lets hope the neighbours don't suss out my shoddy solution!

Did the rotary lock latch replacement fix the problem in the end? And if so, is this an expensive fix (I'm afraid I lack the necessary skills to see to this myself!)?

Cheers!

PS. Did you get a chance to post your "how to" Cokey - this may come in useful?

[cokey]

It's been over 2 weeks since I replaced the Rotary Latch module, and I've not had any false alarms since.

Unfortunately the memory card in my camera had a fit and I've had to format it, without being able to get the images off - so no images of the job - sorry. I have borrowed an image from another forum user, of the latch module inside the door. I've added numbers to it to correspond to stages of the job below.

Anyway, a write-up of how to do the job:

Rotary Latch replacement cost me £80 from dealer
part #:
Drivers side (UK): 51200556767
Passengers side (UK): 51200556770

Diagram of latch and associated parts: RealOEM.com BMW R50 Cooper DOOR HANDLE FRONT/LOCK, SINGLE PARTS

Tools needed:
Torx driver set - sorry don't know the actual sizes
Small flat head screwdriver
Large flat head screwdriver (or better still a rigid, stainless steel kitchen knife from your cutlery draw)

Time to do job:
Took me 1.5 hours but this is because I had to find a suitable way to reattach one of the cables. I found the perfect way so job should really only take you 1 hour. If I had to do the job again, I reckon I could do it in 30mins.

I imagine a garage would charge anywhere between 1 and 1.5 hours but I've not had a quote for this...I'm sure others on the forum have though?

Remove the door-card:

First you need to carefully prise off the bezel around the tweeter and inner door handle. It's one piece and comes off easily using a small flat-head screwdriver.

There are 4 torx screws that need removing. You can see three of them but the forth is behind the small circular reflector. Carefully prise it off with a small, flat-head screwdriver to expose the 4th screw. If your first gen mini was built 04 onwards then another of the torx screws is hidden - see here for instructions.

Now with a large flat-head screwdriver (or better still an old knife from your cutlery draw) you need to carefully prise the door card off. Wrap something around the screwdriver head or knife, to avoid damaging the paintwork - I used an old sock. The door card is clipped in all the way around the edges. I started at the bottom corner at the back of the door and worked my way along the bottom, to the front. A certain amount of force is needed to pop the studs out of the clips but not too much. Once you have done all the edges, you need to kind-of lift the card up, to clear the lock button and out, to disengage it from the clips that run along the window edge.

Now you have the door card off, you are ready to remove the faulty Rotary Latch module.

Have a good look at your new module to familiarise yourself.

Here's an image of the module in the passenger door (of course, could be opposite way around, depending on which door you are working on). Please note: The latch is partially obscured in photo, by the window mechanism (black vertical bar in photo).




Remove the Rotary Latch module

Firstly, reach inside the door frame and locate where the wiring loom connects to the unit - numbered 1 in the photo above. Disconnect the wiring loom from the bottom of the latch module - you need to squeeze the edges to disengage it.

Now you need to take out the metal rod that is your lock button. It's pushed into a round plastic clip type thing, its green in the photo and numbered 2. Push the rod backwards to unclip and then remove the rod.

There are two mechanical cables that need to be disconnected (very similar to the brake cables on a bike). One is for the external door handle, the other for the internal door handle. The external one runs down to the bottom of module - you need to unhook the end of it - numbered 3 in photo. Once unhooked, you need to thread it up and out of the plastic holder. The second one is slightly more fiddly, and can't be seen in the photo. The module has a plastic flap that needs to be opened so you can gain access to the end of the 2nd cable to unhook it. The flap either hinges at the top or the bottom - my old module hinged at the bottom, the new one at the top! Best thing to do is undo the 3 torx screws that hold the module in place, located on the outside of the door edge. This will free the module up and you can manouvere it a bit to get at it and actually see the flap. Prise the flap open with your small flat-head screwdriver and then unhook the end of the cable.

Once you've removed the wiring harness and two cables, and removed the 3 torx screws from the outside edge of the door, that secure the module in place, you can pull the module out. It's a very tight squeeze - keep the module pointing in exactly the same direction as when it's screwed into the door and work it slowly past the black bar (window regulator). It really feels like the module won't fit past this but as long as you have it in the same orientation as when it's screwed in, then with a little wiggling it will make it through. Be prepared to scratch your knuckles up in the process!

Transfer hardware from old to new module

When you have it out, take a good look at where you have to reconnect the cables etc. You will need to transfer the white plastic clip that the first cable went through, over to the new module and also transfer the metal hook that the first cable attaches to - Its just one torx screw - numbered 3 in photo. Make sure the white plastic clip is the right way around.

Reattach cables and install new module

Next thing to do is reattach the 2nd cable. I wasted a lot of time on this part, trying to attach the cable with the module in place inside the door - it's near on impossible! It really needs to be done before you squeeze the module back in. You can do this by unscrewing the 3 screws that hold the inside door handle/tweeter in place and then unclipping it from the door. This will allow you to thread the cable through the door, giving you some slack, and you can pull the cable through and attach it to the module before squeezing the module back in. Make sure you keep the cable on the correct side of the window regulator, otherwise you will get tangled when putting everything back in - you'll see what I mean when you do the job. When pushing the module back into the door, make sure you have it in the correct orientation - the same direction as when screwed in. Slowly wiggle it past the window regulator. Pull the cable back through the door so you can reattach the handle/tweeter.

Now reattach the first cable and thread it through the plastic clip. It's a little bit fiddly - you might find it easier to screw the module back in first, although I managed it with the module free.

Once the two cables are attached and the module screwed in, make sure you snap close the plastic flap. Reconnect the wiring harness. Now reattach the rod for the lock button. It goes in at weird angles but you'll work it out. Make sure you push it into the clip properly - the clip spins round so you can align it easily.

Test thoroughly

Now test that both door handles actually work. Make sure you try them after locking and unlocking the car a few times. The plastic clip that holds one of the cables was getting caught up on the door frame (I put it on backwards by mistake) and therefore the unit wasnt unlocking properly.

Put door card back on

When you're 100% satisfied that it's all working properly you can put the door card back on. Drop it down over the lock button, clip it in along the window, then just push hard around all edges, to clip the studs back in. Then screw the 4 torx screws back in, clip the reflector and tweeter/door handle bezel back on, and you're done!


Good luck!