Vito w639 central locking problem

[ChrisG70]

Hi All,

I have an 09 w639 Vito that has just developed a central locking issue. The van won’t lock with the key fob, I have tried the spare and have the same issue… it will unlock ok but won’t lock.

if I sit in the van and press the button on the dash, it will lock all the doors ok.

I have checked that the interior lights go out after a few seconds when the doors are shut so I don’t suspect the door close sensor… I just can’t get my head around it…

Any ideas?

Thanks, Chris

 

[LostKiwi]

Does it lock if you point the remote at the door handle?

 

[ChrisG70]

Does it lock if you point the remote at the door handle?

No, just been outside to try that, even put the remote right up to the door handle and nothing..

 

[LostKiwi]

If you're anywhere near the Midlands give ReplacementMercedesKeys a call.
I've not heard of this issue before.

 

[ChrisG70]

If you're anywhere near the Midlands give ReplacementMercedesKeys a call.
I've not heard of this issue before

 

[ChrisG70]

Unfortunately not, I am in Yorkshire… it does seem a strange one…

I assume it’s the same unit that is controlled by either the button on the dash or the remote to lack/unlock the doors?

 

[Kev555]

you might still be able to lock the van from the inside ok but from outside the vans not happy with some of the doors it seems. Are no doors locking when you press the lock button on the fob? Not likely its the fob when you tried both and no difference, I take it the battery is good in the spare fob?

 

[ChrisG70]

None of the doors lock with either key fob… but all the doors lock if you press the button on the dash… the key fob will open all the doors just fine…

 

[M80]

I would be looking at the signal receiver on the van,
is that through the windscreen antenna / amplifier?
How is radio reception?

 

[Kev555]

just out of curiosity clean the side door strikers and when door is closed lean your body weight against each one in turn while closed and try pressing the lock button to see if that makes any difference. I think mine still locks the front if theres an issue with the side door striker but worth a try as these doors are multi pin (4 pins iirc) and it only takes 2 wires to operate the internal light in theory, guessing the other two are central locking

 

[ChrisG70]

I would be looking at the signal receiver on the van,
is that through the windscreen antenna / amplifier?
How is radio reception?

It’s funny you should ask that as the radio reception has always been crap but I rarely listen to it so never bothered me… surely that’s a different antenna though isn’t it???? And do you know where it is located????

 

[ChrisG70]

just out of curiosity clean the side door strikers and when door is closed lean your body weight against each one in turn while closed and try pressing the lock button to see if that makes any difference. I think mine still locks the front if theres an issue with the side door striker but worth a try as these doors are multi pin (4 pins iirc) and it only takes 2 wires to operate the internal light in theory, guessing the other two are central locking

I’ll give that a try, however i have had that issue before and it does usually lock the front doors but not the rears when it’s not sensed one of the side doors is closed… the usual tell sign with that is you hear the doors (front) lock but the indicators don’t flash…

in this case there is absolutely nothing when you press the lock button on the remote…

just to add, I have had an occasional issue where it will momentarily tell me a door is open whilst we are travelling but the message then goes away… I wonder if there is a broken wire on one of the doors that is confusing the system????

but…. The bit I can’t get my head around is why it fully locks via the button on the dash?????

 

[M80]

Careful if you clean the sliding door pads, they have a protective coating you don't want to remove. A mild abrasive such as a kitchen cleaner would do it.

The pads can be exchanged o/s to n/s and versa visa. Be sure to tie off the wiring so it doesn't drop into the pillar when unplugged.

Otherwise, no idea where the receiver is. I seem to remember that other models can use the same amp??
The 639 AM / FM antenna is integral to the front screen. The amp is at the roof forward of the o/h front light.
It push stud connects to the antenna.
It requires 12 volts from the HU.
The co ax from amp to HU can be delicate. The inner core can break.

 

[LostKiwi]

It’s funny you should ask that as the radio reception has always been crap but I rarely listen to it so never bothered me… surely that’s a different antenna though isn’t it???? And do you know where it is located????

The antenna is in one of the windows. The signal goes from there to an amplifier (known to fail) and then to the radio and also the central locking system.

Usually when the amplifier fails it won't lock or unlock unless the key is pointed at the IR receiver in the door handle.

 

[Kev555]

Yes LK, your dead right about the aerial in the windscreen as I checked that out a good while back because of bad radio signal, thanks for jogging my brain. Its a thin gold line along the top of the screen and partially down the sides from memory. It connects to the amplifier or connector? up behind the courtesy light.

 

[gawthy112]

Hi All,

I have an 09 w639 Vito that has just developed a central locking issue. The van won’t lock with the key fob, I have tried the spare and have the same issue… it will unlock ok but won’t lock.

if I sit in the van and press the button on the dash, it will lock all the doors ok.

I have checked that the interior lights go out after a few seconds when the doors are shut so I don’t suspect the door close sensor… I just can’t get my head around it…

Any ideas?

Thanks, Chris

Did you find a fix? Mine is the same