Hello Gang,

Recently my 03' Crossfire Coupe has been experiencing an issue with the alarm system. First time this occurred, with the car locked, the siren began "chirping" all by itself slowly going up and down in the pitch it normally makes when it goes off. This occurred only once and was the beginning of the issue. Since then the alarm when locked will sometimes go off with the full normal sounding siren. Unlocking the car turns it off.

Now, occasionally - especially after having driven the car for some time, I lock the car and within 40 minutes or so the alarm goes off by itself. I unlock the doors start the engine for a few moments, shut it off and re-lock the doors and sometimes it will behave itself and sometimes it will set itself off again within 30 or so seconds.

So now I have to keep the car unlocked to be sure it wont go off when I'm not around.

I have had it to a Chrysler dealer (who at first didn't even want to work on the car), a Mercedes dealer and my Mercedes specialist indy, all of whom have been unable to find the problem. My indy did get it to stop doing this for a week or so by "re-programming" the system as he called it. He said sometimes the system can lose its code if the battery is weak and on its way out, however he checked and the battery tested strong on load test.

So, my question is two part:

1 - Anybody have an idea whats going on that could be the cause of the issue?

2-Can the alarm system be disabled so that the car can be locked (either by key in the drivers door, or by keyfob) without arming the system so it won't go off?????

BTW: Car has about 124K miles on it.

Thanks,
-George-

 

Replace the siren, the batteries in it have leaked and the acid is attacking the circuit board.
You could just disconnect the siren, the lights will flash but the alarm will not sound.

 

OK, simple enough I suppose, however wouldnt the circuit board need to be replaced too? I'm assuming the acid from the battery would be damaging the board components...... Is the siren a plug in? Where can one get the siren????????

Thanks!
-George-

 

The siren contains the circuit board.
There are two sirens you can use, one that is the same as the one you have and another that beeps in sync with the flashing lights when you lock or unlock the car.
The siren is shown in this PDF
Sometimes the circuit board is OK and the batteries inside can be replaced, that is cheaper than a new siren. CLICK
The newer beeping siren.

 

Awesomesauce!
So, either siren unit will contain the battery and the circuit board, correct? And will either siren just plug in and mount the same as the original?

Thanks,
-George-

 

Hmmm. got to thinking about this:

The basic issue is that the car alarm is setting itself off after I have locked the car. One reply indicated I could simply remove the siren, but the lights would still flash. This tells me the core problem would not be addressed? I mean, if the lights are just flashing it would eventually drain the battery, siren sound or no siren sound, correct?

So the real question is: would replacing the siren with the bad circuit board remedy the issue of the alarm system setting itself off as I described in my first post????????????????

Hmmmmmmmmmmmm??????????????????

-George-

 

You never said the lights were flashing when the siren sounded, I only mentioned flashing lights because that is the way the car normally indicates that the doors have been opened or closed using the fob.
Using the original or later siren the lights will flash as they always did.
Read the posts in this search to see your problem and its answers.

 

https://www.crossfireforum.org/forum...rm-module.html

 

Can anyone describe the manner in which one can eliminate or remove the siren. Step by step is necessary for me because I'm not that familiar with the Crossfire. American made cars, yes, Mercedes, no! If we can remove the siren, is that going to mess up the other electronics? And, will the lights keep flashing until they run the battery down, as mentioned previously?

I've disconnected the fuse, # 9, but that affects other necessary items.

Anybody with some answers?

Jim

 

The alarm is dead center located in the cowl near the wipers and base of the windshield.

Remove the wipers and cowl screen and unplug/remove siren. Put fuse #9 back in. Job done.

I removed mine cause nobody is stealing these cars.

 

S8MS-01904 - I have to tell you I'm very new to the Crossfire, 3 months new. Is there an electrical lead wire to the siren that can be disconnected? I hate to admit this but I'm 79 years young and am looking for the simplest way of doing this. I tried just removing the fuse, but as you probably know, I lose other functions that I don't want to do without.

You say to remove the wipers and the cowl screen. What is involved in this project? I've heard on this forum that removing the wipers require some special tool. Is that correct? The cowl screen, I presume (dangerous) that is a matter of removing a few bolts. Please correct me if I'm wrong.

I'm sorry to burden you with so many questions but I don't know these cars at all. When younger, I raced sprint cars and then started building street rods when I was getting older. I'm very familiar with American stuff but the Crossfire/Mercedes is all new to me. Hope I don't offend anyone with mentioning Mercedes.

I welcome help from you and everyone else on the forum.

Thanks,

Jim

 

Hey Jim, pretty straight forward. Remove the wiper arms (as on about any vehicle) , then the cowl. The special tool is a security torx bit. You can get them at Harbor freight for about $6. If you want , then just unplug the siren. When you lock/ unlock the doors the lights will still flash ,as they normally do.

 

Thanks Steve. I'll try that!

Jim

 

Hey Jim,
Did it work, just disconnecting the siren?
Peace,
CV

 

CharlieV - I haven't tried it yet. It so cold that I haven't been able to do anything outside. When it warms up a little, I will try it.

I'm finding, little by little, the electronics on this car are a mess compared to normal cars. I learned the other day that the auto door locks that are supposed to lock when you reach 10 or 20 MPH, what ever it is, don't work. I took the car to a Chrysler dealer about a month or so ago because of the siren. Of course they didn't know how to fix it! They said that they tried everything and found the batteries in my key fob were weak. They replaced them ($4.00 worth of batteries that they charged me $20.00 for) and said it was fixed. It's not! And since then the auto door locks don't work. I talked to them again and all they had to say was "Well, they should work!" I left.

Anyway, these cars are great to look at and to drive, but, the electronic's are pitiful!

Jim

 

When the batteries have failed or they are out of the fob for some time the memory of the fob is lost and the fob has to be reprogrammed again, you can do that yourself in a minute. CLICK

Can you lock the car with the key in the door lock or using the lock button on the dash?

You have purchased a car that may have had problems for a long time so you cannot say that all Crossfires are lemons.

 

onehundred80 - I don't know how long the batteries were out of the fob. The dealer did this and I'm not very impressed with their knowledge. I think you and I know more than they do, and I know very little. I can lock the the car with the key in the door, the lock button on the dash and with the key fob. Don't know if that helps you or not. I'm not calling the car a lemon, just saying that I find the electronics in the car very disappointing and troublesome. Same for the Chrysler dealers who seem to have washed their hands with the car.

 

onehundred80 - I forgot to thank you for the information you inclosed under your "click" portion of the message. I copied that and will use it to hopefully solve some of my problems.

Thank you for your inclosure and your input.

Thanks again,

Jim

 

In that list , you'll find that you can program the car NOT to lock when you reach 9 mph. You can reset it. Maybe the previous owner ,wanted it that way.

 

From the List of resettable Crossfire features:

Automatically lock the car at 9mph (15kph).
1, With the key in the ON position, press the interior lock button upper portion for 5 seconds.
Or
2, To deactivate this feature press the lower portion of the switch for 5 seconds with the key in the 'ON' position.