Cannot Lock 1999 C180

[motorhomeroamer]

Started today, walked out and pressed the remote fob to unlock car and the boot flew open? Normally when drive car the doors lock at 10mph which did not happen. When press internal door opening button the boot opens. When getting out and trying to lock doors with fob there are a few whines but will not lock doors but does set alarm. Also somewhere between trying to lock and unlock doors the rear headrests flip down. Car will NOT lock with metal key on fob. This is a new fault today always works fine before

 

[anyweb]

change the key fob batteries and try again, they wear out

oh and read this

http://forums.mercedesclub.org.uk/showthread.php?t=26895

i know it's not the same as your key, but it might be related...

cheers
anyweb

 

[motorhomeroamer]

Certainly worth a try but I forgot to add that even when opening the door normally with the interior door handle ( or pressing the door unlock switch on the dash) the boot opens as well so without any key fob input the boot opens on its own. Have checked operation of the fob and if you press and hold the lock or unlock buttons it will open and close the windows as it should, sets the alarm ok etc its just that none of the doors will lock. Can manually lock the drivers door with the metal key in the fob but it does not lock the other 3....... I am bemused

 

[television]

Your car is all vacuum operated, but actuated electrically

http://www.detali.ru/cat/oem_mb2.as...417717.418&CT=F&cat=44V&SID=80&SGR=045&SGN=03

 

[motorhomeroamer]

So I can only presume that the compressor ( or whatever provides the air ) is working as the boot opens and the headrests go down but the air is not getting to the central locking? Can you suggest anything that I may look for as this started straight away ( no intermittent problems previously) and I am unable to press the door lock buttons down on any door. I am still bemused why pressing any button etc opens the boot

 

[television]

So I can only presume that the compressor ( or whatever provides the air ) is working as the boot opens and the headrests go down but the air is not getting to the central locking? Can you suggest anything that I may look for as this started straight away ( no intermittent problems previously) and I am unable to press the door lock buttons down on any door. I am still bemused why pressing any button etc opens the boot

I would have thought that the fault was in the drivers door lock or with the boot

lock
http://www.detali.ru/cat/oem_mb2.as...417717.418&CT=F&cat=44V&SID=80&SGR=040&SGN=02
The vacuum diagram was in the link, the pump is in the boot.

If the key is pressed then you dhould hear the pump run, do this with the boot open, if the pump does not run, then its an electric fault

 

[motorhomeroamer]

Thanks for that Malcolm, will nip outside now in the seasonal air and have a look. Have tried the link to the web site ( which would show me what I am looking for) but it just times out and then fails. Will try at home tomorrow ( different ISP) as at work at the moment ( they possibly may not let me go to it)

 

[Ellsy Tanners]

Check to see if the pump is water damaged sounds like water ingress into the pse central locking pump.

That would account for the doors and headrests messing around as on the 202 its all pnuematic/ vacum.

 

[motorhomeroamer]

OK, have been outside ( and my goodness it IS a bit chilly) stuck my head in the boot and pressed the key. Can hear the pump running and headrests etc go down so there would appear to be air, just not going to the correct place. Have also found that was not pressing the door lock buttons down hard enough but all other doors are now locked and locked drivers door with key. Alarm sets ok. Will persevere tomorrow when the sun is shining. Now the other doors are locked they will not unlock when key pressed but will get over that later