I have an '05 roadster with about 25,000 on it. The siren alarm will go off in the middle of night for no reason I cannot turn it off and just have to wait for the alarm to stop. At times it will reset itself and go for 10 mins at a time. I took to dealer and they kept the car for over a week and of course they could not find anything wrong.

Today the alarm went off 4 times.

Any ideas?

Jim Sawyer

 

Do you park on a hill???

 

Nope the car sits in the garage and it is flat and level.

Jim

 

Seismic activity? You tried to turn it off with your keyfob? Can you set it off then turn it off with the key?

 

I set mine off inadvertantly about twice a month. The car is in an attached garage, the key in my pocket. If I'm wearing jeans and squat down or lean across a counter; there it goes. Its got a great range. Of course what's happening is the "panic" button's getting squeezed. It is kind of surprising, as setting off the siren is the last thing on your mind.

If yours is going off "in the middle of the night" then that's not it. (I assume you are not up). Are you sure the garage is secure? Do you have any pets with garage access? Good luck. Slo

 

As I type this it is 5:30 in the am. The keys are hanging up on a hook and I am no where near the car and guess what the siren is going off. The neighbors are complaining (the car is in a dead flat garage which gets no colder than 50 degs) I am almost ready to let some one other than me be the proud owner. Please I need some help on this.

Oh I forgot siren cannot be turned off with key fob it goes until it has pissed off the whole neighborhood.

 

some old threads that may be helpful:

https://www.crossfireforum.org/forum...ighlight=alarm

https://www.crossfireforum.org/forum...ighlight=alarm

From the manual page 1,215...

'ALARM TRIPS ON ITS OWN'

Possible Causes:

FALSE GLOVE BOX SWITCH SIGNAL
FALSE LIFTGATE LOCK SWITCH SIGNAL
FALSE HOOD AJAR SWITCH SIGNAL
FALSE LEFT DOOR AJAR SWITCH SIGNAL
FALSE RIGHT DOOR AJAR SWITCH SIGNAL
FALSE IGNITION SWITCH SIGNAL
FALSE BRAKE LAMP SWITCH SIGNAL
FALSE ANTI-THEFT TOW SENSOR SIGNAL
INTERMITTENT CONDITION
For a complete Vehicle Theft Security System Circuit Diagram, Refer to Page 8Q-44.


~ some other threads stated... to make sure the glove box, console, hood, trunk, roadster cover and both doors, etc... are closed tightly.

 

Okay so here goes the latest. Alarm still goes of whenever it feels like it - but the dealer (the third one I have been to) says wow that goes off all the time. So they said it is a door switch? Okay I said , now we are waiting on part from Germany. I guess no one will be able to figure this out.

 

Would it be possible to unplug the siren until the dealer fixes it?

 

I would disconnect but I don't even know where it is located. I had thought about taking a fuse out but the circuit powers other stuff.

 

I am having very similar problems with my crossfire. I replaced the battery and checked my fuses and is still cant get it to stop going off in the mornings (even if i driving to work).

Have you been able to fix the problem? and if so, what was wrong?

I would like to be able to drive my car with confidence and pride again (rather than embarrassment :P)

 

Siren is bad!

 

having the same problem. after some checking, it's likely the siren. after checking my alldata information for my slk, it is located under the air intake, the plastic cover under the windshield wipers, and is located on the passenger side. I will order a mercedes part #003 542 68 20 which is for a 98 slk to save a little money and is supposed to cost about $45. A cheap and easy try and I will let you know if it does the trick or you may want to just go ahead and try yourself after what you've been going through because it is an inexpensive try. BTW you might pull the negative side of your battery with the alarm deactivated at night to make the neighbors happy.

 

after removing the siren this morning, the part # is A 171 820 25 26 and is a Mercedes #. The windshield wiper arms require a puller to get off. Unbolt the siren from inside the engine compartment on the firewall, the nut on the siren bracket is welded on. on ordering, the part # has changed to 219 820 32 26 and is about $170 and you will need a wiring harness that the dealer will provide at a small additional cost to adapt.

 

I couldn't wait for the siren to come in to make sure this was the problem, so I robbed it off the base model we have and after 24 hrs no siren. I'm concidering it fixed until the Xfire tells me otherwise. If something changes I'll let you know.

 

Did this permanently solve the problem for you?

 

yes, problem was solved by replacing siren or you can just disconnect it.

 

Hi all, I am having the same problem. I called the dealer, and they gave me 2 parts. The horn itself and the control module. Which unit was the problem?
It seems like the alarm battery dies out and the lights just flash, or the alarm will blare out and I cannot silence it on command. On a side note, has anyone replaced their fog lights, the price they gave was pretty expensive for 1 light?

 

Had a similar problem a few months ago and found a post in the forum that suggested that it could be a failing battery. Took the car to a trusted local battery retailer and replaced the original (2005 w/70K miles) with a new one and it stopped the nocturnal alarms. Might look into that...

 

Where is the siren located?