Hello everyone.

I'm trying to get my car back home after I had to leave it at work tonight. It is a 2004 Coupe. I went out to the car after work and hit the unlock button on the fob and noticed that it didn't work. So I figued I'd just unlock it with the regular key and figure it out at home. I unlocked the car and go to get in and the alarm sounds when I open the door. I try and get it to stop by turning on the car and it tries to start but then dies a second later. I did that a few times, and eventually now it won't start at all. I went back into work and bought new batteries for the fob (conveniently I work at Home Depot) and put them in. I then tried to do the same thing and still it won't start at all and the alarm sounds when I open the door. After some searching I think the problem may be that the fob died and now it's not being recognized by the car. What is the process to re-sync the remote with the car?

I'd really appreciate some help if anyone can assist.

 

Did you try the second key/fob?

 

I don't have one unfortunately. I recently purchased the car and the dealer only had one key.

 

Worth a try...

• Ensure that the doors, hood, decklid and rear liftgate are properly closed. The alarm cannot properly arm if any of the doors or other openings are not closed.
  
  
• Replace the batteries in the key fob to ensure that the remote is capable of arming the alarm system. If the batteries have been dead for more than a few minutes, the fob will need to be synchronized with the vehicle to function. To synchronize the remote with the car, aim the remote at the vehicle and press the lock or unlock button twice. Next, place the key in the vehicle's ignition and turn the ignition switch to the "On" position. All of the steps must be completed within 30 seconds.
• Verify that the parking lamps flash three times when the system is armed using the remote. Alternatively, verify that the alarm is armed by looking at the alarm indicator on the dash. If the alarm is properly armed, the alarm indicator light should blink.

 

I will try that. The thing is that as soon as I open the door, the alarm is going to sound and I'm not sure if that will affect anything with the resync of the fob.

 

Just went back down to work to try your suggestion, and it didn't work. It's like the car doesn't even recognize the key fob at all. Won't lock the doors or open them up. I tried a few other things that I found online to no success either. I guess I'm just gonna have to call my dealership tomorrow and ask. I tried to call tonight but the service department was closed, and the guy didnt know anything that did answer the phone.

 

The fob batteries are only used to transmit a signal that opens and closes the doors etc. This is the only function lost if the batteries are not working in it for some period of time.

The car alarm system will be armed simply by locking the car with the key even when the fob batteries are dead. The pointing key ritual only co-ordinates the fob to the transmitter. The chip in the fob is what allows the car to start with the proper key in the ignition.

The Central Locking Pump/Security System Module in the trunk is the item that arms the alarm. If this module is damaged or otherwise at fault the alarm system is compromised.

The SKREEM module also can go haywire and produce similar results. If the SKREEM does not recognize the chip in the fob the car will not start.

You may have water under the foam in the trunk and that has damaged the CLP/SSM, or the SKREEM module has gone belly up.

Search for SKREEM and Central Locking Pump/Security System Module problems.

 

It seems rather odd that one of those two systems would act up right when the fob stopped working. I used the car a few hours earlier, and everything was fine. And now I can't get the key fob to do anything to the car, and even the unlock button inside the car doesn't do anything.

 

https://www.crossfireforum.org/forum...tml#post430634

Could it be RCM - Mystery no start?

Quote from post "Symptoms being car will die and/or will not restart but may restart after waiting for a while. Also, when attempting to start the engine all electronics work but the engine will not crank. "

 

Not a RCM problem as that wouldn't affect the alarm. Sounds more like the SKREEM module died and that's what caused the FOB to stop being recognized.

 

Mine did the same thing and it turned out to be the console switch was turned off and the car thought it was being towed. it is like the second switch from the right side. Thumb the switch a couple of times to make sure it is OFF, then try the FOB.

 

I tried doing the alarm switch, turning car to run, hitting key fob, hitting the interior unlock switch. Nothing works. Had it towed to the dealership this morning and they said that they will look at it tomorrow. So I will check back in once they diagnose it. I think it may be the central locking pump thing though like someone mentioned. There is nothing I can do to get the doors to unlock other than manually do it with the key in the door. And even when I do that the alarm sounds. I just feel sorry for the mechanic that has to work on it and have the alarm go off every time he opens a door.

 

IF I recall correctly. In a Crossfire, this is one symptom of a low voltage battery and low voltage plays hell with Mercedes electronics.
Is this the original battery?

 

I'm not sure if it's the original battery or not.

I just got a call back from the dealership saying that they have a diagnosis. They're saying that there are two issues. The first is that the key is basically bad so they have to replace that. And also that the ignition cylinder is grinding into the housing, so they're going to have to replace that.

Does this make sense as to why the alarm would keep going off though? Anyone have any ideas about how legit the diagnosis is?

 

I vote bogus diagnostic.
I wouldn't think the key / ignition lock would cause the alarm to go off and also not allow the car to start. To me, it points to a receiver ring / SKREEM issue.

 

They called back about the insurance, and said that it looks like it's going to be covered. When I asked to speak with the mechanic to ask some things I got the runaround. I then mentioned that I've never had anything wrong with the key and she said whoops, he actually said something about the SKREEM module having the issue. Something about the immobilizer not letting the key start. Would this also cause the interior unlock key to stop functioning?

 

That, I do not know.

 

Well, after they replace the key, key cylinder and skreem and you still have problems.
Try a search here useing key fob and alarm.

 

Is the SKREEM the module that makes the chirp when the fob is clicked? I read that replacing one of the alarm module with the newer version will make it chirp, as it didn't used to.

 

That is correct, the newer alarm modules will chirp. The SKREEM does not do the chirping.