key not working

[madbonky]

hi there,

i have a w203, 2002 year, the spare key has had new batteries but still does not work, i dont know if the pcb board is faulty in the key or what else what it could be, any ideas? The key works fine in the ignition, starts the car all ok etc. Has anyone else any expierience of this problem?

 

[Menz-Benz]

It probably needs reprograming, it should tell you how in the owners manual.

 

[fjmrf]

It can probably be 2 situations:
- A blown fuse in the boot (number 8 if I well remember) with needs to be replaced (I try a 7.5, 10 and 15A, and it only worked with the 15A, probably because some problem with the alarm siren (the siren is working, but not so loud));
- Reprogram the key to use RF (radio frequency):
put the key on the place, turn to position 2, turn back and take out. Press and hold the close button on the key, press 5 times the open button, release both, press close button.

This two proceeds have worked for me.


Cheers

 

[boisty]

I have a similar problem with my 05 w203. Both keys work but need to be very close to the drivers door handle tooperate the locks. I've replaced the batteries in both keys but the problem remains.
I have read on other posts that this problem may be related to the radio and indeed the radio reception is poor especially on fm stations.
I have spoken to the previous owner and he seems to think that both problems occurred at the same time.
The posts I have read about this have baffled me so far as I'm a bit of a dunce when it comes to electrics.

 

[mexican gaz]

Hi you can not reprogamme das 3 keys which the 203 as, sounds like only working on infrared if need to be close to drivers door handle. There is a fuse in rear sam that can blow needs to be checked.

 

[boisty]

Hi you can not reprogamme das 3 keys which the 203 as, sounds like only working on infrared if need to be close to drivers door handle. There is a fuse in rear sam that can blow needs to be checked.

Hi Gaz

Thanks for the info but not really sure what you mean by "rear sam"?

 

[boisty]

Hi Gaz

Thanks for the info but not really sure what you mean by "rear sam"?

I've found the fusebox and found that fuse 8 was blown. Replaced fuse with a new 7.5 amp fuse and the cdl initially worked fine off the remote. I then checked the radio, which again woked fine but then went to lock the door with the remote and the problem was back (had to use the remote close to door handle).
Checked the fuse and found it blown again and when i replaced the fuse again it blew immediately.
Can anyone tell me what i should be checking next please????

 

[EZS]

Its usually the alarm siren. In the inner wing!