Alarm D-I-Y notes - The BMW X3 (E83) Forum

I just finished an alarm install on my two-week-old X3, and I think all went well. (I'll only know for certain after I have it programmed.) Here are a few notes for anyone thinking of doing this:

1. Don't consider this unless you are willing to work carefully and remove parts like the cabin air filter housing under the hood and wedge them back. Under the hood, things are very much like the 3-series cars so you can get some idea what to expect from web sites such as www.bmw330ci.com/DIY_Alarm.htm and www.my330i.com/mod8.php
Overall, I probably spent 2 hours, working slowly as this was my first BMW operation. (But I do have lots of old sports car repair experience.)

2. Be nice to the parts person at your local dealer and ask for the instructions when you buy the alarm kit. They printed the instructions for me with no hassle. (I also asked for and got a discount from MSRP.) If they won't give them to you, either (i) shop somewhere else or (ii) ask me to fax the instructions to you.

3. Tools needed: #30 Torx driver, 10 mm socket & extension.
Tools recommended: high-quality trim panel remover and heat source (see below).

4. The three components can be installed separately and, seemingly, in any order. Here are a few specific hints:

(The instructions now say to disconnect the battery. I ignored this to avoid any memory loss in the radio, nav, etc.)

(a) The ultrasonic sensor goes in the roof module with the controls for the sunroof, etc. Pry the panel off from the rear with a good, clean, trim panel tool. I did not have to fish for the connector. In my car it was hot-glued to the cover. I didn't have a heat gun and couldn't find my glue gun, so I CAREFULLY used a soldering gun to melt the glue.

(b) The tilt sensor goes under the forward panel in the cargo area. Use the trim panel tool to remove the 4 plasic rivets. I couldn't see how to remove the panel, so I propped the rear up with two long screwdrivers. (Does anyone know what the big, unused connector there is for?)

(c) The under-the-hood part (the siren) required the most effort and some brute-force pulling (and pushing on re-assembly). Don't try this if the engine is still hot! I did this last on the off-chance the siren would trigger, but it didn't.

I'm willing to give more advice. But, if your dealer charges a reasonable price, I'd probably recommend that most people leave it to the pros.

(2.5 auto, bluewater, gray leather, PP, nav, privacy, xenons, and now an alarm--my first new car in 28 years)