Hi all I have search everywhere and still not getting an answer

I have an 03SL55AMG R230 not keyless go
1) When I went to open the car the other day with the key fob, nothing happened, first thought flat battery in the boot, so used manual key
2) Could not get into the boot even after starting car and pushing boot release
3) Check PSE fuse and it was blown, replaced and new one also went, manual key for boot also not working so broke the high up break light and got in
4) Dismantled PSE and replaced pump motor, changed fuse. PSE all working, boot soft close and unlock switch in car all work including the central locking
5) Still car fob not working with either key, changed both batteries in key and still nothing
5) I then noticed that the car would lock and unlock using one of the keys fobs inches away from the driver door handle sometimes, but not at all on the passenger side
6) Searched for a solution and concluded there is an issue with the IR sensors on the passenger side.
7) Drivers side works about 1 in 10 time so I guess it is also a dry solder in that sensor
8) Checked both keys and they same result, (can see light ok on key flash red when pressed and using the phone camera can see the light at the end of the key as well)
9) I have check all fuses behind seat in the car where the PSE one was and they all look fine.
10) Tried all the suggested key resync options but still nothing(not sure which one work on this car)

Has anyone done the soldering the board of the IR? I found a video about this on a C and E class
I believe the car has 2 systems one IR and one RF
Has anyone else seen this before and know if there is another fuse or something else that might control this?
I guess it is a visit to dealer if not

Thanks

 

Yes, and because of the limited range of IR I imagine you want to get the RF portion working. If that's the case, unfortunately I don't believe there is anything simple to check.

When you press a remote button an antenna module demodulates the signal and passes it to the overhead control panel (OCP). Then it is communicated to the ignition switch via the CAN for processing. If the switch determines the RF signal from one of the vehicle's keys, then the PSE pump is signaled via CAN to lock/unlock the car. If you have Star Diagnosis you can see whether or not the demodulated RF signal is reaching the OCP.

If the OCP module had a blown fuse or were completely dead, then obviously none of the overhead lights would work. And if the antenna module failed, you'd have no FM radio.

The complete set of electrical wiring diagrams and part locator for the R230 are available as a 150 MB download: R230 ETM 64. Since the drawings contain ActiveX controls, you should get a warning that they could be malicious. And since the package was distributed by Mercedes-Benz, I think you can trust its content. I suggest you have a look at diagram 80.20-U-2050KA to begin with.

 

Thanks for this, are the two system independent or each other?
Could this have been caused by the PSE failing?

 

Hi, i was just wondering if you found out what the problem was in regards to this post? I am having the exact same issue with an 2009 SL63AMG.
Any suggestions would be much appreciated.
Cheers.

 

What about the alarm siren that shorts out and blows the antenna fuse? Every Mercedes I have has done this and the fob only works within inches of the door handle sensor. The radio will still pick up fm stations, but not that well. I recall going through this with my sl55 a few years back and unplugged the siren and inserted a new fuse. It was good, but has no siren for the alarm. The siren is the same for many different models and is about $150, but the car locks and does what it should now.

 

Thank you. I do know that the siren works, as it went off when i tried a few things with the key fob etc, but i will see if i can find it and disconnect it. Finding the correct fuse is a problem because i can't find any info in the book about their location/ function etc.

 

I solved my by changing
Antenna Amplifier Front Right MERCEDES BENZ SL R230 55 AMG A2308201189
I got this from Ebay and then it is located behind the dash on the drivers side for right hand drive cars and passenger side for a left hand drive. You can get to it from the foot well, but it is a bit of an effort and you need to get behind the padding.
Hope this helps

 

How did you determine that it was the Antenna Amp?