R230 Sl350 20014 - remotes (RF) not working

[jezworld]

R230 SL350 2014 - remotes (RF) not working

Strange one this and I'm familiar with hammering through forums to try and find solutions but this has stumped me.

R230 350SL (2004) I have two remotes that have worked flawlessly for 2 years in my ownership.

Left one remote in the ignition one day (BBQ) and noticed the next time I had to lock the car it wouldn't remote lock or unlock the car.

Realised that the car can be locked and unlocked perfectly fine (with either remote) via pointing key at little window on door handle (so IR locking is working fine)

Is this a:

1) Fuse problem - checked the areas I thought it would be but suspect there's another fusebox that I can't track down.

2) Key fob reprogram issue? I understand there is a process for reprogramming these by pressing buttons numerous times whilst in the ignition or pointing at rear view mirrors etc? If anyone knows what this process is I could try that.

However both keys are working with the IR locking/unlocking so I know both remotes batteries are ok.

3) Locking pump - we know this is working fine as the keys work with IR.

Anyone help who has heard of similar issues with their SL?

My rear boot is dry as bone (yes I'm lucky as I know water can get in the boot and crap out the pump there) and the car has operated perfectly for 2 years with no problems so its obviously something I have done.

 

[grober]

http://dl.dropboxusercontent.com/u/1168411/Model 230.pdf

 

[jezworld]

Thank you - appreciated. It explains what is going on process-wise (pretty much what I fathomed I guess).

Any idea what fuse may be related to the amplifier? My assumption is that this amplifier is separate to any other parts of the car as everything else is working fine.

 

[BlackC55]

Look in the rear fuse box. It is under a flap in the "back Seat" compartment behind the drivers seat.

If the fuse has blown it is probably caused by a faulty PSE pump. Quite often the pump is faulty because it has got wet due to boot leaks. There is a guy on ebay that can repair them. New they are £900.

 

[jezworld]

Very very helpful - have found the chap on ebay if this is what the issue is. Thank you so much.

Will update on here if I find the solution.

 

[lxi]

Very very helpful - have found the chap on ebay if this is what the issue is. Thank you so much.

Will update on here if I find the solution.

It's not the PSE if it locks via IR.

If the PSE goes down you have no lock or unlock (or comfort seats or soft close boot)

 

[jezworld]

It's not the PSE if it locks via IR.

If the PSE goes down you have no lock or unlock (or comfort seats or soft close boot)

Was wondering that as yes you are right - its all fine. No dampness in boot - foam dry and pump works fine. All locks go up and down via IR no sweat and boot works fine (boot close is a bit temperamental sometimes)

 

[jezworld]

Can anyone indicate what the procedure would be to program the key to work on RF (if at all?) Can keys "forget" this frequency for some reason?

They work perfectly on the IR side of things (unlock, lock and roof down and ignition start).

 

[lxi]

You should read the manual (very carefully) - there is a section somewhere about synchronising keys. I can't remember the conditions under which you are advised to do this, but obviously if it's in the manual it's not necessarily something terminal.

From memory, it involves putting the key in the ignition at position 2 & pressing two buttons simultaneously (I think lock & unlock), but that might be slightly skewed.

For the sake of a frustrating half hour trying to find the bloody section, it's worth a try !!

I'll see if I can find the bit as I've been there before

ps - this might all be for keyless models only - not sure

 

[jezworld]

Thank you mate - I have been through the manual but must have missed that. Its odd as its not the kind of thing that I imagine they'd want users to play about with (knowing mercedes)

 

[grober]

There's a suggestion on this thread it might be one of the CL rf antenna amp module/s- Unfortunately its/they very difficult to get at- its/they are behind the dash!!! You would have to be sure that's the fault before embarking on such a labour intensive repair?? Time to get plugged into Star maybe?
Central locking problem - Mercedes-Benz Forum

 

[jezworld]

Yes think that's inevitable.

Just reading through manual at moment to see if anything I've missed.

 

[lxi]

I added a ps later above you probably didn't see - the synch act might only be for keyless which (as you left your key in the ignition!) you probably don't have but do make double sure re the manual

 

[jezworld]

Yes mines a normal key'd model :/

 

[Tedwud]

Hi. Did you every get this problem sorted out? I've got the same fault with mine now. It's in at Mercedes and they've told me now they don't know what's wrong with it. Any help would be appreciated.
Many thanks
Edward

 

[fitch]

Hi Ted

No I didn't pursue it to get fixed in the end as the IR still works - as in I unlock/lock the car and pull the roof down fine by simply pointing the key at the door handle. the RF seems to have gone kaput on the remote side of things - did you find a solution yourself?

 

[richard]

Assuming car is pre mid 08 facelift, fuse is 5A fuse 57 in the fusebox under the rear right hand side compartment

The antenna amp (right side behind dashboard at bottom of windscreen, impossible to get to without removing dashboard), has a data-feed where remote signals are fed to whatever deals with them (I can't remember whether that is the OCP or one of the SAMs).

I'd imagine that if the fuse was gone the radio reception would be naff though.

Of course it could be the amp, the keys, the wiring, the controller that decodes them, and this would take some investigation with the keys, the car and an oscilloscope to check the data, but the dealer should be able to figure this out.

R

 

[fitch]

Thanks Richard.

Been coping since but it would be nice to get it sorted.

I'll print off your suggestion and next time its in I'll see what they can fathom.

I imagine its quite a common issue - just like the constant consumer battery drain issue that seems to be commonplace too.

 

[Michelten]

I know this is an old thread, but I would like to ask fitch, Tedwud and jezworld if you guys were ever able to fix this issue. I have my SL350 2003 with the same problem: only the IR seems to work, not even 100% of the times. Any comments will be appreciated.

 

[Gareth04]

I know this is an old thread, but I would like to ask fitch, Tedwud and jezworld if you guys were ever able to fix this issue. I have my SL350 2003 with the same problem: only the IR seems to work, not even 100% of the times. Any comments will be appreciated.

I have the same problem, 2004 SL350, IR is fine, I have bought both RF modules that fit under the dash, but will try to get it on STAR somewhere first to see if there is a more obvious issue, although with the IR working to open the doors its looking like the RF amp - no issues with radio interference or anything like that - I'm in no rush to start stripping out my dash either, I have a copy of WIS, but can't find where the dash disassembly section is