Factory Alarm Troubleshooting

[CalicoNC]

I recently brought a factory alarm for my e34. It's the Alpine model with the three button remote. Everything works fine, "EXCEPT" i cant get the horn to sound. I pressed panic to see if the alarm would sound, and the lights just went crazy, but no sound. I switched the button in the module to siren, and i still did not hear anything. I dont know where the horn is located, how it looks, even if i have one. Nobody seems to want to help me out. My car was pre wired, so i thought the horn/siren was already installed. Does the horn have a fuse or harness that i would need to connect? Im kinda lost.

HELP!!!!

[colink1]

The horn or siren would be under the front cowling, behind the expansion tank. That's if your car was pre-equipped w/ the OBC horn or Alarm siren. Sounds like you have neither. The connector then should be under the hood, in front of the left wiper (driver's side).

[CalicoNC]

So what does the horn/siren look like. I see two horn like things on each side of my aux fan. Is it safe to assume that this is not what you're talking about? Also, what does the connector look like that you were describing. And last but not least, what is a "cowl"


P.S. " I dont have the full obc, it only has Date, Temp, time, and the buttons to set them. Could this be the reason i don't have the OBC horn?"

[kalevera]

There is a DIP switch on the alarm box. One of the switches controls whether the alarm uses the car's horn or its own dedicated horn.

Not all cars were wired with the dedicated alarm horn. In fact, in many cases where the alarm was installed at the dealer (the vast majority of these systems), the dedicated horn is not in place, because the additional pay that the tech got for installing the horn was miniscule. E32s are the exception -- I think it made sense to install the horn in that case (they are usually installed on the firewall, by the wiper mechanism, under the grates). A prewired car does not mean that the alarm horn is in place, just that the harness connector exists for the alarm box.

Keep in mind that having the dip switch set to use a dedicated horn, without having that horn installed, is supposed to short the system. Never seen this happen in practice, but was always told that it is the case... So, if the DIP switch is set as such, you may have a bad system.

[CalicoNC]

thanks lowell that was the info i was looking for. I will have a look to see what's going on under the hood.


EDIT:::


Is this the connector you were referring to by the windsheild?, If so, I guess i dont have a siren. Anyone know how much they cost from the dealer?

[Qsilver7]

You can see what the horn looks like for this system in the pic below...and since you don't have the "full" OBC with the CODE function...you don't have this horn installed.

The horns you see up front by the aux fan...are your car's horn (when you press the horn on your steering wheel). The "cowl" as you've figured out by now...is the "wall" between the engine bay and the cabin of the car.

Everyone is different...but I find the audible alert annoying and turned mine off. You can "hear" the doors lock and unlock from about 10-15 feet away...that's all I need....for me, the horn is overkill.



Just an FYI...starting in 1993...all e34s came wired for the alarm...and all e34s (EXCEPT the 525i sedan) came with the alarm unit installed (VPC).

[CalicoNC]

thanks Qsilver good info. I just wanted the siren so i could hear if my alarm went off. The only thing that happens now is my lights blink like a son-of-a bi**h! Any info on how much a siren would cost? Would any siren fit the connector...etc....?

[CalicoNC]

Could this horn be used with the alarm or not?

http://cgi.ebay.com/ebaymotors/ws/eB...m=110134770548

[CalicoNC]

Can anyone help me with the horn i posted above. Is it compatible?

[Qsilver7]

Sorry, can't say definitively if it will work...but if you look at the electrical connector of the horn you linked us to (see pic below)...compare that to the elelctrical connector at the end of the wire you found under your hood (we can't see the end of it clearly).



When you look at the diagram in the online parts databases FOR THE ANTI-THEFT SYSTEM...(see diagram below)... #8 (which looks like what you would need) isn't listed anywhere in the part nbr index...so I conclude that it is no longer available...but #5 IS listed. (#5 = BMW part # 61 33 1 379 090)

http://www.bmwmobiletradition-online...65&fg=60&hl=30

The horn you linked to on ebay...looks more like the horn in this diagram below (#2) which is for the car...not the anti-theft system: http://www.bmwmobiletradition-online...61&hg=61&fg=40

[CalicoNC]

thanks Qsilver, i managed to track down the person i brought it from off of ebay. He still had the siren. Managed to get it for $12 (shipping included!!)

[mottati]

the Horn #5 in the above diagram is what came standard on "most" e34's, the alarm siren was an optional extra when you added the security system after the fact. Like mentioned above, if you don't have the high level obc with code function, you likely don't have the horn.

I had a 92 525iTa, bought in 94 or so, added the security system myself, and was lazy and didn't add the siren, because i already had the horn. So when you set the alarm, it would go "beep" and "beep beep" (kind of sounded like the road runner) on arm and disarm, rather than "chirp" and 'chirp chirp'. Was good enough for me.

[CalicoNC]

Just got my siren today. The siren doesnt have a connector, just two wires, one red, one black. I tried plugging them into the connector by the windshield, nothing happened. I was thinking black meant ground, and red meant that it was the power wire. The connector by the windshield had two wires also. A black and brown wire leading to the connector itself. I had the alarm module set to "siren", and I had the "beep" set to "on". I jammed the black wire to the corresponding one and the red to the brown wire. Still no sound. Here's a visual of the connector from the windshield

[CalicoNC]

Siren wires:

[mottati]

on a bmw brown is pretty much always ground.
Maybe try switching the wires? Brown to black and black to red?

[CalicoNC]

okay, i'll try it out

[Qsilver7]

Calico, do you have a Bentley Service Manual? I ask because it has the Electrical Wiring diagrams.

It could be possible that you have the wrong electrical connector. Since you don't have the full OBC which has it's own horn/siren...there may be another connector for the anti-theft alarm when it is added on later as an accessory.

I don't have an e34 Bentley with the wiring diagrams...perhaps someone who does...can look it up to see how the accessory siren/horn is connected versus the one that's hooked up in conjuction with the full OBC.

Just a thought.

[CalicoNC]

oh, just an update, i got it to work. Come to find out that brown was the ground and black was the power. I had it backwards. Thanks mottati.....now if i can just stop it from going off for no reason.lol