I own a 1999 528i e39 BMW. I purchased it used. This car has brought me a lot of joy until recently. My job has me scheduled to wake up and out the door at 3 am. The problem is when I use the key FOB to unlock my door ( button 2) the alarm sounds waking my neighbor, their dogs/cats birds and everything in range. I tried reprogramming the key FOB and it seemed to work correctly for the first of many times that I have reprogrammed it. I am not sure that I am programming it correctly or the alarm itself is faulty. Must there be someone familiar with this issue that can give advise on what I can do.
Are you referring to the siren or the chirp?
Ed in San Jose '97 540i 6 speed aspensilber over aubergine leather. Build date 3/97. Golden Gate Chapter BMW CCA Nr 62319.
The normal alarm failure is the underhood switch - but that's for an alarm that goes off randomly, so... not your case.
Thing to try #1: Does the false alarm happen if you open the doors w/ the key in the drivers door instead of using the remote? If that works then at least you have a work around while you try to sort it out and not have your neighbor slash your tires.
If the alarm goes off when you unlock the car like this, it usually means that the "DWA" (alarm) module is somehow not getting the "disarm" signal... but then via its sensors, it sees all the doors actually unlock and says "WAIT A MINUTE! DOORS AREN'T SUPPOSED TO BE OPENED YET!?!?" Basically when it sees the doors are all unlocking without having been disarmed, it thinks somebody is slim-jimming them or something... they aren't supposed to unlock without being disarmed so... BLAAT BLAAT BLAAT
On my car I had this problem (alarm going off on unlocking) when my 'P-bus' (one of numerous communication buses in the car) was shorted out and not working. Unfortunately that's a bit of a PITA to test and diagnose and if its shorted out, a PITA to track down where and how it is being taken down.
Thing to try #2: Do your steering wheel buttons to the radio all work OK? Does the center-lock button work to lock/unlock all the doors? Do the remote mirror and window buttons (i.e. for the passenger side) and the seat position memory all work OK? If all those functions work then the main comms buses in the car should be working alright. If some of those aren't working it at least gives us a telltale that there's a comms bus issue someplace.
It could also be that the GM (general body electrics - door locks and windows etc.) module is bad, as the GM is the brains behind all the remote-lock, alarm, door/window functions. It could be 'just bad' internally, and not passing the unlock message along to the DWA, or, it could be failed in some way that shorts and takes one or more of the buses down. That would be easier to test if you had a 'known good' GM to try.
Another thing I'd personally do would be to scan the GM for error codes and see if it is registering any faults. Easy for me to say but for that you'll need to find somebody with a true proper BMW scanner (not just a generic 'OBD' engine scanner...) that can talk to the individual modules inside the car.
I feel your pain - this really sucked when it happened to me and I'd inadvertantly set it off at night trying to get something out of the car while my super-early-sleeping-and-waking neighbor (basically he is on your schedule) was asleep in a bedroom like 50ft away from the car.
2003 M3CicM6 TiAg
2002 540iT Sport Vortech S/C 6MT LSD TiAg
2008 Audi A3 2.0T DSG (the daily beater)
2014 BMW X1 xDrive28i (wifemobile)
Former:
1985 MB Euro graymarket 300SL
1995.5 Audi S6 Avant (utility/winter billetturbobattlewagen)
If you want to turn off the sound acknowledgement when you unlock/lock the car so you don't wake the neighbors, it has to be coded using OBD software. This is can be done by the dealer or you can do it yourself, but you will need the following:
Windows notebook (I recommend Windows XP/7 32-bit but some have gotten other Windows versions to work.)
BMW Scanner with PA Soft 1.4 ($10 on eBay, search for "BMW Scanner 1.4", includes cable and software)
20-pin to 16-pin adapter, because you need to use the round under hood adapter ($5 on eBay, search for "BMW 20 pin 16 pin")
Open up the BMW Scanner and jump pins 7 & 8
Once connected, the Scanner will allow you to change the alarm setting.
Here's a tutorial on using PA Soft: https://forum.e46fanatics.com/showthread.php?t=1067835
In the meantime, if you want, just pull the fuse for the alarm horn. The fuse is located in the trunk... or at least it is in my '97. Check your fuse charts.
Unless its a pre/post facelift thing, the siren has a battery backup of its own and at least in my case the fuse pull would not stop the alarm from sounding (BMW really did a good job on the alarms on these cars...) I suppose if I let it go off for long enough to kill the battery it might work but that was gonna be super painful...
2003 M3CicM6 TiAg
2002 540iT Sport Vortech S/C 6MT LSD TiAg
2008 Audi A3 2.0T DSG (the daily beater)
2014 BMW X1 xDrive28i (wifemobile)
Former:
1985 MB Euro graymarket 300SL
1995.5 Audi S6 Avant (utility/winter billetturbobattlewagen)
I know 'nuttin about a battery backup for the alarm. All I know is that pulling the fuse stopped my occasional alarm ('97 528). But, because I don't know if I have a battery backup or not, anything I'm writing is of zero help
The horn is inside the passenger side wheel well, right? I think I recall that is where it is from when I changed my rear suspension.
Yep, right rear wheel well, behind the liner to the rear
Last edited by BimmrMeUpSnotty; 09-14-2018 at 08:57 AM. Reason: Stupid phone...
Set the controls for the heart of the sun
Is the battery inside the horn? I didn't look at it super close, once I figured out what it was... by searching on this site!
Yes, the battery is inside the alarm module.
It's mounted up high to the rear of the LR wheel, about 5" in diameter.
Remove the wheel and then the liner and you'll see it.
OK, then either my '97 doesn't have the battery, or the battery is dead. At 22 years old (actually 23 as it's a '96 build date)... I think I know which answer I'm going to go with!
Bookmarks