1991 bmw 735il

[josh2L8]

i got my son a used bmw 735il 1991 (his first car), radio doesnt turn on, engine feel strong and need a bit of work on the interior. driven it for about a day, when i got home front passenger door locked and anti theft was triggered...annoying horn just keep going with hazard light on(5 minutes) . this happen when i put the key on the ignition or open the door. the key they give me dont have any button to disable the alarm...engine will crank sound like a strong battery , it seems that anti theft prevent me from starting the car ...how do i correct this problem and to permanently disable this feature...i dont want this happening again..especially now that i bought myself a 1993 740il...........HELPPPPPPPPPPPPPPPPPPP

[josh2L8]

no reply at all...i guess its not really an active forum k,,,ill get my answer from another site.........

[lincolnmaster80]

You are right...this isn't a very active forum. As far as I can see, there are only about four other members who participate on this forum, and I seem to be the only one who is subscribed to the 7-series sub-forum and respond regularly. I don't usually check it very often throughout each day but I do get updates and will respond the next day if I'm not away from home.

Anywho, do you have the OBC VI next to the radio? If so, does it flash " - - - - " and is the red LED lit up next to the CODE button? There are two horns installed. One is the OBC horn and one is your driving horn, the one you activate with the steering wheel.

You should have the OBC VI in your model year and should look like this:


If a code was entered, enter the code to unlock the car. When the code is entered, the OBC will prevent the car from starting and will sound the OBC horn, though I'm not sure for how long. If you don't know the code, there's no way that I know of to retrieve it through a "back door". Aside from that, just try all the numbers from 0-0-0-0 to 9-9-9-9 and you can enter any code you want when locking it.

If the car is installed with a factory alarm system and this is what is making the alarm sound, I'm afraid the only way (that I know of, at least) to disable the alarm is with the fob. I believe in that model year, they still had the IR (infrared) remotes, but I'm not completely sure. They still had them in my 1990 year. Your 93 740's alarm system went to RF in that year and used a different fob, which I believe was built into the key bit itself.

The fob I think you might be looking for looks like this (far right):


The black box (right) with a blue connector is the IR control module and is located on the left side of the car under the rear seat. Top Center is the reciever in the roof (see pictures below for difference with or without sunroof). Bottom Center is the dash grill LED for programming the IR remote fob (left).

IR Reciever with sunroof:


IR Reciever without sunroof:


Dash Grill LED:


If you have those components installed, then you need to put out an APB for a used fob. Buying new can be quite expensive. As I live in Canada, to get one from BMW cost me $356 CAD which included the key bit. It is ordered directly from Germany with key bit. It is a switchblade style unit. You can usually pick up a used one for $300 less! Usually on eBay. I will put out my feelers and see what I can turn up for you. I phoned a BMW dealership in the states and it would have only cost me $200 without key.

The BMW part numbers for the key fob and key bits are listed:
66 10 1 390 263 - Switchblade style key
51 21 1 388 909 - countersink screw to hold key
41 21 1 956 925 - laser cut key
32 32 1 151 013 - Factory original Varta batteries, but cheaper ones you can buy at your local Wal-Mart.

Keep in mind, the part numbers that are different that the ones I listed, the correct ones are the ones listed above. They are the most up-to-date.

[josh2L8]

thanks for the info, well it turn out that since i dont have the fob i have to hold the key (driver side door) to the left toward the front of the car...for a good 10 sec it shld clear it....now i dont want to go into that hassle so how do i disable it....since i dont have the code for the obd

[lincolnmaster80]

Originally Posted by lincolnmaster80

Anywho, do you have the OBC VI next to the radio? If so, does it flash " - - - - " and is the red LED lit up next to the CODE button?



If you don't know the code, there's no way that I know of to retrieve it through a "back door". Aside from that, just try all the numbers from 0-0-0-0 to 9-9-9-9 and you can enter any code you want when locking it.

Well, I'm not sure, but before you start, make sure the OBC isn't flashing at you to enter a code. If it isn't, you're in the clear. There is no factory set code for the OBC so whatever code you enter, is completely up to you...just remember your code! Like I say, I don't know of any way to retrieve a forgotten code.




How to set the OBC code:
1. Turn your ignition to Position 1 or Position 2
2. Push the CODE button on the OBC
3. Enter any 4-digit code that you desire
4. Push the S/R button to set the code.
5. Remove key from ignition and code is now set and car will not start with the ignition key.

To disable OBC lockout:
1. Turn your ignition to Position 1 or Position 2
2. Enter your 4-digit code and push the S/R button
---OBC is now uncoded.

You might find this page handy.
BMW 7-Series OBC CODES - Hidden OBC Secrets

[josh2L8]

thanks, i could start the car again now....since i been trying to lock and unlock the door....now the passenger side door remain lock trying to open it from the driver side ..it just wont open if i go outside (passenger door) and open it with the key it will trigger that alarm again....what the hell can i do to just kill this alarm permanently....

[lincolnmaster80]

You might want to try a resync of the door locks. Basically, lock and unlock (don't dead/double lock) about 5 times. If this doesn't work in the drivers door, do it in the passenger door. Make sure that all the door pins are in the unlock position when you do this.

You might also try an emergency unlock procedure. I'm not sure if it works for just the drivers side door, just the passenger, or for both front doors, but it's worth a try.

This is what you do:

http://bimmer.roadfly.com/bmw/forums/e32/3775411-1.html

[josh2L8]

thanks , believe me i tried seach first....but that link is really helpful....thanks again........hey nice pic of ur car....clean

[lincolnmaster80]

Thanks! I'm practically in love with my car!

You might try registering at roadfly and ask about disabing your alarm. The user, 'highline' seems to know quite a bit about the E32 alarm systems...