And so it goes….
 

Was going to post in the “What did you do for your X5…” section about my R and R of the ignition switch this am, which went great, to a point. The only odd thing was the new switch wasn’t quite clocked correctly when I broke it out of the box. So I turned it another quarter turn, approximately, with a screw driver to match the position of the old switch, and installed it with no problems. The car starts and drives fine, no codes, etc. I’m not sure if it will fix my random SES light and other occasional gremlins and codes that pop up, but the switch was 20 years old so it couldn’t hurt.

My euphoria of another BMW job well done was quickly shattered by the alarm going off approximately 1 min after I locked it. I repeated this several times…unlock, lock, alarm goes off after a min or so. No codes and everything is showing closed, locked, powered, immobilized, etc. I pulled the hood switch pug and it still goes off.

Could I have gotten the wrong switch from FCP, or installed it wrong? It’s a super simple job tho. Thoughts would be appreciated. In the meantime I’ve pulled the alarm fuse (13 in glove box) and it runs, locks, etc. fine. I need to go to work in a few and the car will be at the airport for several days so hopefully there won’t be any parasitic drain of some sort.

As I recall, there is something about pushing the key fob buttons in a particular manner that turns off "pet mode". Our Golden Retriever used to set off the alarm when he jumped around wondering why he didn't get to join us for an ice cream cone...

Press the alarm button twice. It should turn off the interior motion sensor.

My first thought too, but I tried that and it didn't work unfortunately. The alarm goes off about 1 minute after locking/arming with and without the motion detector activated. Thats not to say the motion detector hasn't failed, but how randomly coincidental would that be to fail at the same time I replace the ignition switch?!

I thought perhaps I screwed up and there were two different switches, one for cars with alarms and one for those without, but RealOEM only shows one PN for "ignition switch", and I don't recall that the X5 was offered without an alarm.

There's always the chance that I broke some brittle 20 year old wire or connector when replacing the switch this am, or that I screwed up by rotatign the new switch to match the "clock" of the old one, but I can't see how the new one would have mated to the barrel that extends out and engages the switch barrel, when the key is turned. The two only mate when both are clocked correctly.

I just did this repair a couple of weeks ago and like you I had to rotate the new switch one click clockwise to match the old switch. TIS nor the youtube vid I watched didn't mention this but seemed like a good idea. I used a Febi. No problems so far and solved a whole bunch of codes. I almost didn't get it fully inserted and realized this as the set screws went beyond their original depth. I backed the screws off and gave it a good push to get it fully in.

My ignition switch was replaced with an OE one and didn't have to "clock" it to line up with the old one. May be this is a Febi issue? :dunno:

Update...
I pulled fuse 13, drove it to the airport and left it for a 5 days. I was worried there would be some parasitic drain, but the car started up just fine so it looks like fuse 13 fully disables the alarm system, and not just the siren.

I plugged the fuse back in this am and locked the car to see what would happen. The LED light on the mirror started flashing, but no beep when I locked/unlocked the car. Also, the alarm hasn't gone off yet, which tells me that the system is broken or needs to be reset somehow. My new theory is that replacing the ignition switch was viewed as a power interruption by the alarm system which, I think, triggers the siren. Pulling the fuse perhaps put the alarm system into a standby or other dormant mode that now it needs to be reset from...maybe...perhaps?

I'll plug the foxwell in and see if I can get a reset, or test of the system. Beyond that I think the only thing I can do is pull the negative from the battery and wait a while, which will reset everything.

Update
 

After sitting at the airport for 4 or 5 days with the alarm fuse pulled, I go the car home and plugged fuse 13 back in. The alarm LED works fine and behaved like it should, however the arm/disarm beep wasn’t working when the car was locked or unlocked. On the plus side the alarm wasn’t going off anymore after a minute or so. After driving it this way for a week or so, and another trip to the airport, my suspicions of a failed 20 year old siren battery were now even stronger, so I ordered one from FCP.

Not kidding when I say the next time I drive the car that day, the alarm beep on lock/unlock worked fine, and has continued to do so. Amazing.

At any rate, she’s getting a new siren. Any gotchas to this job? I can’t imagine there is any software issues are there? My plan is to pull fuse 13 and with the car unlocked swap the new siren in.

siren, or not
 

My alarm system is probably malfunctioning, or incomplete, as I can't find a siren underhood. So I'm interested in your problems as stated here.

When I first got my X5 last year, I had only one failing diamond key, and set off the alarm several times (and once or twice, since). The "clown's nose" flashes rapidly, the headlights & tailights start flashing, and the horn beeps (sometimes, not always), but never a siren.
Attachment 82629

While reading your problem post, I looked up siren in NewTis, and saw that there should be? a siren underhood, on the left side, near the brake booster. Mine has nothing there, not even a mounting bracket. Missing, or never installed? Realoem shows two types, but neither present on mine. I can't find anything amiss using my Foxwell, except for two undefined faults in the ZKE. The lights flashing are enough for at home, but I'd like a reliable horn sound and/or a siren, for when it's parked in a bad location.

Workingonit, you are correct in that there should be a siren there assuming your car had the factory alarm system. I am not sure if any e53 x5s were sold without alarms, but I sort of doubt it. Mine (siren) sits exactly where you describe and is strangely easy to get to, for a BMW!

When I got to the airport today I locked the car and was walking away when whaddya know, the alarm went off. It had been behaving perfectly for several days. It’s the little gremlins that drive me nuts with this car. Fuse 13 is back out… Hopefully the battery in the siren is in fact failing and triggering the alarm, rather than having to start chasing wires for shorts, etc. I considered the motion sensor could be failing, but the alarm still goes off when I double-clutch the key lock to turn the sensor off.

Happy to send you my questionable siren to troubleshoot with if you want, after I get the new one in next week.