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Frank87
12-12-2020, 07:40 AM
Background:
- could not unlock my car with the remote;
- unlocked manually, alarm activated and sounded the horn;
- pulled the rear seat;
- unplugged the alarm computer;

The car now drives without alarm.

I have a spare alarm computer that is deactivated. It is exactly the same unit. Plugging this in won't let me re-initialize the keys but will not sound the alarm either.

I have used a universal computer to pull codes (Launch X431). All kind of alarm codes erased in all modules.

I now see the following with live data:
- boot closed / open, the sensor always says closed. Probably a faulty sensor or tampered wiring;
- driver door closed it says "IDLE";
- driver door opened it says "DEACTIVATED;
- passenger door closed it says "FAULTY";
- passenger door opened it says "DEACTIVATED";
- tilt sensor always says "OPEN";
- bonnet and rear seat say "OPEN" and "CLOSED" depending on being open / lifted up or not; <- THIS PART WORKS

The words IDLE, DEACTIVATED, FAULTY and OPEN are probably not original BMW terms but it is the way how this tablet reads the live data. I need the boot sensor to say "OPEN" and "CLOSED" like the bonnet sensor does. I need the tilt sensor to read different when I move / turn it around and I need the passenger door to do the same as the driver door. This will confirm the entire alarm system works.

Questions:
- how do the sensors in the door work, where can I find these sensors? I want to check the wiring on the passenger door or replace the sensor;
- where is the sensor in the boot located?;
- how does the tilt sensor work (near amplifier in back) / how can I manually test it? Unscrewing it and moving it around does not change the live data;

shogun
12-12-2020, 09:46 PM
On my E32 the crash tilt sensor is located under rear seat left/driver side inside the seat frame, the blue one here , crash sensor http://bmwe32.masscom.net/johan/electronics/rearseat.html
I assume (?) on the E34 it is in the same location. I have never disassembled one, once someone mentioned that there are metal balls inside , old system tilt sensor balls explained https://www.rfwireless-world.com/Articles/Tilt-sensor-basics-and-Tilt-sensor-types.html

on E39 and E38 the tilt sensor is located in the trunk http://www.bimmerboard.com/forums/posts/564650

But that is the crash tilt sensor and not a alarm sensor.
Check here in the EBA list for the info of options to install a DWA alarm, the EBAs usually show the list of components and where install. Download those EBAs, that site was dead for more than 1 year and could disappear again
http://www.ow.no/index.php?option=com_wrapper&Itemid=34