bmw 735i alarm problem

[Kar]

Total newbie, so i hope i have not missed a similar post. I have a problem with my 735i's alarm. It keeps triggering and I can not figure out why. I lock the car and after a while the alarm triggers for no apparent reason. I have this car for over a year now, and never before has it done this. I use a key to enable and disable the alarm and not a remote. I have checked the battery and it is fine and fully charged. Does this alarm (original alarm) have a siren battery as well or does it draw power directly. This is a problem as I can not go anywhere as I can not lock my car. Is there anyone that can help with this problem.

[shogun]

Kar,
most of the E32 experts are here. Maybe you ask the question there
http://www.bimmerboard.com/forums/e32/
In addition you should indicate if that car is U.S. spec. or European spec.
Also indicate which month/year the car has been produced, as this is important to look into the right wiring diagrams.
To find out the production month and year, visit my website below and search for VIN decoder. Just input the last 7 digits of your VIN and you will get those details.
Add that info as your signature on bimmerboard. (under "my account" on top you can add that).
Do you know what kind of alarm system you have?
There was once a problem like this
http://members.roadfly.org/smoothy/False%20Alarm.pdf

The alarm horn is on passenger side (LHD) in the space next to the wiper motor. It dies not have a siren battery. All power comes from the original battery under rear seat. There is usually (depending on the system) a microswitch on top of the cover of the battery. So if the alarm is switched on and someone wants to cut of the battery and he lifts the rear seat, the alarm will go on.
Have you see such a switch? Maybe you misalligned it?

[Kar]

Thank you for the advice I will post there as well. As far as your question U.S. or European no clue, bought the vehicle in South Africa if that helps. The car is a 92’ model vin no. 0DB45593 (got this info from the reg. papers) and as far as the alarm system, only that it is the original one the car came out with. When I put my sound system in about 8 months ago, I noticed that switch, it was broken off so I took it out. This did not seem to have any affect on whether the alarm went off or not so I left it out.
What I did notice as well yesterday is that when you lock the door, when you turn the key to position one the doors lock, turned to position two the alarm enables, yesterday I wasn’t able to lock to the first position as the locks kept kicking open. I eventually got this right last night, so my car is locked at the moment but the alarm is disabled. Thanks for the link to the pdf but this didn’t help me. This problem has me licked.

Did register with the site you said and it has been a while and no cofirmation email, my email address was definitely correct. Does this usually take so long or am I just being impatient. thanks again for the advice

[shogun]

Think about tome difference, they are sleeping in some parts of the world now and will reply.
That is important that you mention that the car is from ZA:

I have checked you VIN :
735i, ZA model, RHD, automatic, cat: NONE (very seldom), production date: 08/1992.

So it might be of interest what kind of alarm system you have installed.
Maybe that is different from the EU or US versions.

[shogun]

If the doors open again after you lock them, you might have a problem with the microswitches.
Check here under 'body
http://bmwe32.masscom.net/
doorlock, microswitch etc.

[Kar]

What’s meant by “cat: NONE (very seldom)” ? As for the alarm all I can telll you is that is the original factory alarm installed. EU or US version I wouldn’t have a clue. If you turn the key to the right once you have unlocked the car, this switches the alarm off (microswitch) this doesn’t seam to have a problem. The problem seams to lie on the actual central locking system. Lock position one kicks the door locks open after a while lock position two locks the doors but activates the alarm which then goes off after a while. But strange thing is if I start the car a couple of times until the auto lock works and the doors stay lock, then I can lock the doors and everything works well. But lately this is very rare, so something is malfunctioning or wearing out.

Didn’t occur to me about time differences as I thought the responses were automated

Thanks for the link it was quite helpful, a lot of info there. At least I understand the mechanics of the door a little better now. To send your car in to someone to repair a problem you have absolutely no idea about always is an extremely expensive procedure. It helps to know what the problem is even if you can't fix it yourself.

[shogun]

Cat: none = that is very seldom that a catalyst is not installed in an E32.
I only know from some early E32 in the U.K. and Italy, where a catalyst system was an option, but mainly all E32 have a catalyst.


Lock position one kicks the door locks open after a while

I assume that something in the door system is broken or not functioning. Microswitchtes, doorlock bracket, See the link I posted before.
The system is like this: the GM= general module gives the signal to the RM= relay module, from there the doorlocks are actuated thru the microswitches and motors. Then there is a feedback to the GM that doors are actually closed. If the GM gets an opposing signal = for example one door still open, then the GM opens all doors again to signal to you that something is wrong.
This kind of safety function was eliminated on later GM only. They stay closed and do not open again even if there is an opposing signal.

Here is the full info on the new GM which was used from 09/1991:

-Repeat and time interlock for headwashers, time interlock 3 min.
-headlight washing pump at fifth windshield washing after time interlock
-intensiv washing pump operating at reduced time from 3 to 2 seconds
-minimum interval for wipers reduced to 2 from 3 seconds (programmmable)
-increased wiper contact pressure during windshield washing now also provided

-previously the GM would react opposing signals (e.g. an unlock signal while trying to lock, as with a defective microswitch) by carrying out the first command (e.g. locking, followed immediately by unlocking). Repeating the first command then results in carrying out the command, e.g. try to lock again, and locking is now carried out. This function (Asynchronious Position)is omitted in the NEW GM.
-After unlocking is performed due to crash sensor activiation, the locking command is now reactivated by double-locking with the key from either side (driver or passenger door).
-The one-touch operation of windows has been expanded to all 4 windows in OPENING direction. Drivers side has one touch in both directions
Sunroof is not already in the tilt position.
-switch off delay of the interior lights after entering the vehicle and closing the driver's door reduced from 20 to 15 seconds.

PS: do you still have trouble to register at Bimmerboard?

[Kar]

Thanks again for the advice Shogun, It looks like I have my work cut out for me. I suspect the problem may lie with the front passenger door, as this has been giving problems when locking for the last two days. Maybe in the long run it will be better to replace the alarm with a different one.

[Kar]

I still have no response from Bimmerboard

[shogun]

On top of the board there is a link 'contact moderator'. So send a message to David Cecil, tell him under which name you have registered.
Address it to David Cecil, because I also get a copy as moderator, but I cannot do anything as moderator. David is the webmaster.
Look for broken cables in the door where they go from the A-pillar into the door. That is sometimes a problem
http://www.pagaduan.org/bmwe32/Kabelbruch_Tuer_links_hinten.htm

[Kar]

I will do so, on both accounts. thank you