Alarm with a mind of it's own

[Nic_s]

I'm posting way to much here... :nono:

Anyway, as the title states my alarm in the 540 tends to have a mind of it's own from time to time. To have this looked at I need to leave the car at our local Alarm & Radio place for a whole day. I would like to try and and find the issue myself if at all possible. I was hoping some Fanatics might know what I can look at.

As I'm typing this I remember there was a fuse under the back seat that wasn't really blown, just melted (Green 30A fuse). The auto electrician that took a quick look at the lighter sockets found it. I have replaced it with a spare. Could such a fuse have been the problem?? I haven't used the alarm since last week so I don't know if the new fuse made a difference. I really just made the connection.

 

[Jandre]

What is the alarm doing/ not doing?

Mine just does not want to make a noise. Hazards go bonkers, but she is as silent as a ...... well... just silent.

 

[Nic_s]

It would make noise for no reason. Other than that it seems to work fine... it would just go off for no reason. It did it once and about 1 min after I turned it off and on again it did the same. Testing something like this where I live is somewhat annoying because of all the noise. :mmm:

 

[Jandre]

Many moons ago my ex had a Mazda 323 with an alarm system that went off whenever it felt like it.

The alarm was triggered by faulty door switches (the ones that switches the interior light on and off when you open and close the doors).

Replaced all of them and it was all good.

On the e36 I had a similar problem and that turned out to be a damaged trigger switch on the bonnet. Fixed that up and all is good.

 

[Nic_s]

Maybe a proper clean might help :dunno:
If it doesn't, I'll have to have it looked at. I might end up replacing things that don't need replacing. If they are pretty cheap I might just do that, but knowing the Dealers it probably won't be. In that case maybe the Alarm and Radio place could be of some help.

 

[Jandre]

I don't think you have to approach the dealers for this. Car Audio Warehouse sorted mine out, so I guess you can go to any of these car audio places.

 

[zaleonardz]

Folks,

Again this is where the power of diagnostics comes in.

On DIS, there is an alarm interrigation software, part of the ZCS/body electronics (Yep, even on the old E34)

On here is allows you to test the unit itself, test the sensors, switches, it will tell you where, if there is a problem.

It could be that one of your contacts is faulty preventing the alarm from not arming,

I doubt its that burnt fuse, as the alarm is incorporated into the body electronics, which also controls things like windows and stuff... It could be the fuse, but one never knows.

On my E39 I have a spook alarm, for no aparant reason alarm would just go crazy, only in the day time, temp related, DIS the car, bonnet sensor trigger 30 times or more.. there is the problem, bonnet sensor replace, no guess work...

The E34 is older though, so finding somebody with an ADS cable is tricky, maybe zeemax or Rick... ?

---

Wait

How far are you from bloubergstrand ?

 

[Nic_s]

Folks,

Again this is where the power of diagnostics comes in.

On DIS, there is an alarm interrigation software, part of the ZCS/body electronics (Yep, even on the old E34)

On here is allows you to test the unit itself, test the sensors, switches, it will tell you where, if there is a problem.

It could be that one of your contacts is faulty preventing the alarm from not arming,

I doubt its that burnt fuse, as the alarm is incorporated into the body electronics, which also controls things like windows and stuff... It could be the fuse, but one never knows.

On my E39 I have a spook alarm, for no aparant reason alarm would just go crazy, only in the day time, temp related, DIS the car, bonnet sensor trigger 30 times or more.. there is the problem, bonnet sensor replace, no guess work...

The E34 is older though, so finding somebody with an ADS cable is tricky, maybe zeemax or Rick... ?

---

Wait

How far are you from bloubergstrand ?

---

About 60 - 70 km, but I'm guessing.
Do you have any more info on how the Diagnostics work (What software and cables you need or would use)?? I don't have any experience with Diagnostics as the only way to diagnose the 318i was by ear. :hammerhead:

We have a independent BMW specialist that should be able to help, but I'll try MSaich (Used to work for BMW) first and see if he can help.

EDIT: I just saw on M Saich's card that they do Diagnostics and Coding.

 

[zaleonardz]

+1.

You would need an ADS based OBD cable and DIS, which is a frikken biatch to get working....

I would just take it to your local diagnostics dude, and see if he can pick up comms with the system, from there it should tell you. If not, and the unit is fried, you may just be better off with a full aftermarket alarm.

 

[ashley]

My Alarm played up as well, set itself off at any time
Turned out to be a faulty door sensor.
Just an idea.

 

[Sankekur]

Well, leonard diagnostics are indeed a powerful tool, but there is also not replacement for some old school debugging. When I got my car the alarm was also doing its own thing, had the codes read but the guys just said it could be this or that... grated they might not have had the kind of equipment you have, but in the end I took my service manual, checked what the alarm system looks like and ruled out things until I got to the bottom of the problem, was the bonnet switch (that is what is the cause most of the times it would seem)