go to the your local forums and see if anybody can reset the alarm using a bmw reader/scanner.

 

Is the alarm OEM or aftermarket? Odds are it's a malfunctioning/oversensitive shock sensor.

 

This happened to me and it was a low/dead battery that caused the alarm to randomly go off.

 

it's not uncommon for the hood sensor to go bad and have issues. check that. i forget if our alarms will show which sensor was triggered by the blinks. i thought it did.

have you done any work on the car lately in the fusebox? reason i ask is my 2000 323Ci had a crazy alarm issue when driving which was traced back to the fusebox having a stress crack. but mine would go off while driving. yours sounds like it's only when it's parked.

 

You have a interior motion sensor. If the wind blows anything hanging from your rear-view mirror, the alarm will sound.

 

Yeah it only happens when it is parked. I had the radiator replaced recently by a freelance bmw mechanic. Also I had an issue with the hood not closing so I had to replace the wire and latch for the hood. I think its hood related because the hood would not close properly, so I had to slam it hard to close, before. I also had the power steering pump replaced not too long ago.

 

Its not aftermarket...

 

Should I get the battery recharged, or? Maybe start there?

 

Hey atleast ur alarm works. Ive nvr heard or seen the clown nose on the bottom of the rear view mirror flash once.

 

http://forum.e46fanatics.com/showthread.php?t=895898&highlight=hood+sensor+alarm

 

i know you can disarm the interior sensor by pressing lock the second time (within 5 seconds of locking the first time). you can try that and see if that helps. if not, it's probably one of the other sensors like the hood or a dying battery

 

Aw you beat me to it, OP you can try doing this

 

Check your hood sensor. I had this same issue on my e39 at the time. Disconnected sensor, problem solved.

 

This used to happen on my 2000 328ci and it was beyond annoying! I don't know if I have any sure fast answers, but I can tell you what worked for me.

First tip: you can still lock all the doors by putting the key in the door and turning to the right I think. It's the normal way that most people lock their cars who don't have the clicking button mechanism, but it took me a long time to realize that when it happened to me because I was so used to just using the button on the key fob.

Back to the issue: I tried a ton of things and eventually something must have worked because it stopped after a long while of annoyance.

1. I unplugged my interior motion detector.
2. Unplugged the tilt sensor in the trunk for a time period. Thing I replugged subsequently.
3. I think I also happened to get a new battery around that time because it finally died after a while. Maybe that was the cause or the result of the alarm going off, not sure.
4. I noticed after reading threads on the issue that many people, including myself, had this usually happen during the winter months. This was really odd and for that time period I just had to manually lock my doors.
5. Finally, now it doesn't go off randomly but maybe once or twice every couple months for no reason and it seems like those are on cold days.

I haven't been able to figure it out for sure and I haven't read anything definitive on the forums, so I wish you the best! :thumbsup:

 

I haven't been able to figure it out for sure and I haven't read anything definitive on the forums, so I wish you the best! :thumbsup:

You need to have the fault codes in the general module read by INPA or GT1. That will tell you exactly what set it off and how many times up to 31. There is a lot of talk on the forum recently about PA Soft 1.4, but it does not tell you the # of occurrences for each fault code which I find very usefull when diagnosing such problems. Carsoft sucks in this respect too. I found old PA Soft 1.3.6 better in this respect since it showed the # of occurances in the parameter column although it took a little mental decoding of the hex number.

 

Open the hood, press the Hood Closed Switch so the car thinks the hood is closed, arm the alarm system. Manually manipulate the switch until the alarm sounds. Consider the switch alignment for the possibility that some adjustment might be in order so that the hood holds the switch better.

Just a guess here, but me thinks that your hood switch is mal adjusted, and it wavers between making and breaking as the car heats and cools. You also have stuff such as interior motion sensors that might be seeing racoons, whatever, walking around on your car. There is so much that you have not told us that it is very difficult to know what the problem is. Since you have had work done under the hood that caused somebody to actually touch the hood closed switch, then I would suggest you start there.

 

raccoons walking on your car would not trigger the interior sensor.

 

I would have to agree with the sensors going out, either tilt or interior

 

+1 on hood sensor issue. And +1 on pressing the lock button twice to deactivate the alarm and still lock the doors.

 

Pushed the lock button twice on my way into the liquor store tonight......and within 10 minutes, everybody was looking out the door to see what all the whoooping was!

Should there have been any kind of sound or something happen after the SECOND push, just so I know that it "made contact"?

(Whatever was supposed to happen, apparently didn't happen. Doh!)

 

Hi guys ,l got 3 series 2004 320d UK model.
The alarm started going crazy for about one week.
The battery seems ok, cleaned the interior and the bonnet sensors ,still nothing.
So I had to lock the car doors manually one by one from inside .
For the boot l used the key but l couldn't lock the diesel cap .
So annoying .
Any ideas ?

 

Disconnect the hood/bonnet switch and see what happens.

 

Thanks a lot for the quick response.
For how long for should l leave it disconnected ?

 

For at least a few days, the hood/bonnet switches are known to cause false alarms, the switches go bad.

 

And if the alarm STILL goes off (on .......what is the NEXT most likely culprit?

Thanks,
ms

 

I just had same issue, pasoft pointed out the Hood switch as well, replaced it and alarm problem solved.

 

Where did you get it........and how much?

Thanks for any info, bud!

 

Thanks guys ,I really appreciated your help.l will do that first thing in the morning.Hopefully that's the issue.
Probably if l took it to a mechanic they would charge me hell lot of money.
And they would have kept it for a day or two.
Love this forum.
Thanks again.

 

I had a similar issue and it turned out to be the anti tilt sensor. That is the module located in the right rear quarter panel behind the trunk liner.
I bought one on eBay and that solved my problem.
I used INPA to diagnose the faulty unit. I don't think BMW sells the module so you may need a used one.

 

I will try that as well if everything else fails.Cheers

 

I'm wondering if something as small and "innocent" as those fabric strips on the inside of the windshield posts flapping could cause the alarm to go off. (What ARE those strips covering, by the way? Are there air-bags inside/behind those little strips? And when those fuzzy fabric coverings lose their adhesion and start to constantly fall off or just swing in the breeze......what can they be replaced with? Mine are taped up with double-sided tape right now.....and they look like crap!!)

Thanks for any tips. (On the strips AND the alarm.)