Do you have a spare remote, if so, does it behave the same and only work close up too?
Check fuses also.
The remote unlocks the car by IR (infrared) and RF (radio frequency)
The IR needs to see the receiver in the door handle and so the remote only works close up.
The RF will work far away, around corners and through walls, the RF signal is picked up from an amp at the rear window which also handles the car radio signal. The top 2 or 3 lines in the back window are the aerial.
A bit more on the subject here… http://www.mbclub.co.uk/forums/electronics/126804-loss-central-locking-radio-signal-question.html
Dec
Check fuses also.
The remote unlocks the car by IR (infrared) and RF (radio frequency)
The IR needs to see the receiver in the door handle and so the remote only works close up.
The RF will work far away, around corners and through walls, the RF signal is picked up from an amp at the rear window which also handles the car radio signal. The top 2 or 3 lines in the back window are the aerial.
A bit more on the subject here… http://www.mbclub.co.uk/forums/electronics/126804-loss-central-locking-radio-signal-question.html
Dec
Dec
Thanks for the reply. Apologies for late thank you. Christmas and New Year. Both keys react the same. They only work when next to the door handle. The fuse for the rear window screen RF detection can you tell me where it is located please. Any ideas what else could be wrong ?
regards
Mark
Thanks for the reply. Apologies for late thank you. Christmas and New Year. Both keys react the same. They only work when next to the door handle. The fuse for the rear window screen RF detection can you tell me where it is located please. Any ideas what else could be wrong ?
regards
Mark
Is your car alarm working properly, I seem to recall something about the alarm being connected with the fuse for the amp.
Test the alarm by locking yourself inside the car, stay motionless for one minute then open a door/s or bonnet, the alarm siren should then sound and the hazards should flash, deactivate the alarm by unlocking the car with the remote or putting the remote fob into the ignition.
Don’t know where the fuse boxes are in your car but it should say in the user’s manual.
Were the remote fob batteries changed recently, maybe the need replacing?
Dec
Test the alarm by locking yourself inside the car, stay motionless for one minute then open a door/s or bonnet, the alarm siren should then sound and the hazards should flash, deactivate the alarm by unlocking the car with the remote or putting the remote fob into the ignition.
Don’t know where the fuse boxes are in your car but it should say in the user’s manual.
Were the remote fob batteries changed recently, maybe the need replacing?
Dec
Dec
Car alarm works fine. The batteries in the fobs are new.
Pointed key fob at rear window screen but no reaction.
"television" suggested removing the fuse for 15 mins for the rear SAM to reset the SAM. No sure if this works or which fuse it is.
It could be that the RF antenna amp is broken. Have read it is either in the head liner or rear passenger (UK) pillar.
Any suggestions ?
regards Mark
Car alarm works fine. The batteries in the fobs are new.
Pointed key fob at rear window screen but no reaction.
"television" suggested removing the fuse for 15 mins for the rear SAM to reset the SAM. No sure if this works or which fuse it is.
It could be that the RF antenna amp is broken. Have read it is either in the head liner or rear passenger (UK) pillar.
Any suggestions ?
regards Mark
V12
MB Enthusiast
Yeah, amp in rear pillar is a frequent problem for lots of cars of this age.
V12
MB Enthusiast
It's been a while but I recall you pop out the top front edge. It has 2 pressure fit clips and then 2 or 3 hooks half way down which unhook as you pull the trim forwards and upwards. Has a couple of locating tabs on the bottom as well, but those came out naturally.
Just don't force it and it'll come easily without breaking clips.
Just don't force it and it'll come easily without breaking clips.
Have read a lot about fuse 8 in the boot. It feeds the SAM unit.
However, there is no fuse box in my boot next to the GPS and CD unit. Lots of talk about the alarm horn causing the problem. Would like to eliminate these before I start taking the head liner down. Thank god for this forum !
However, there is no fuse box in my boot next to the GPS and CD unit. Lots of talk about the alarm horn causing the problem. Would like to eliminate these before I start taking the head liner down. Thank god for this forum !
V12
MB Enthusiast
Fuse for SAM is under the rear seat, where the SAM also is.
Little drop down panel under the drivers side rear seat.
Little drop down panel under the drivers side rear seat.
You can only pick off the easy things first in the hope its something simple like a fuse or a bad connection, maybe poking the roof lining in the hope of getting lucky and hitting a loose connection. Can’t help with the fuse locations, someone else might chip in here.
It might be worth unpluging the alarm siren even though it seems to be working, the are known to go faulty around 10 years of age of age, presumedly your siren is the original and hasn’t been replaced since new.
After reading the below link you might be better off getting an independent to put it on star if all else fails.
Some sensible advice from our man in China, here… Headliner removal to fix remote RF locking - Mercedes-Benz Forum
For reference, picture of used Mercedes W220 S430 S500 S600 rear roof rail glass antenna amplifier OEM… W220 Mercedes S430 S500 S600 Rear Roof Rail Glass Antenna Amplifier | eBay
A bit technical this here… W220 antenna system and Key Fob - Mercedes-Benz Forum
Your fault today will by my fault tomorrow so let us know the cause and the cure of this.
Dec
It might be worth unpluging the alarm siren even though it seems to be working, the are known to go faulty around 10 years of age of age, presumedly your siren is the original and hasn’t been replaced since new.
After reading the below link you might be better off getting an independent to put it on star if all else fails.
Some sensible advice from our man in China, here… Headliner removal to fix remote RF locking - Mercedes-Benz Forum
For reference, picture of used Mercedes W220 S430 S500 S600 rear roof rail glass antenna amplifier OEM… W220 Mercedes S430 S500 S600 Rear Roof Rail Glass Antenna Amplifier | eBay
A bit technical this here… W220 antenna system and Key Fob - Mercedes-Benz Forum
Your fault today will by my fault tomorrow so let us know the cause and the cure of this.
Dec
Before you ask… Where is Alarm Siren on W220 - Mercedes-Benz Forum
Only unplug the siren with the car unlocked otherwise the siren will sound off, powered by its own internal back up batteries. Every thing else will still work without the siren.
Dec
Only unplug the siren with the car unlocked otherwise the siren will sound off, powered by its own internal back up batteries. Every thing else will still work without the siren.
Dec
