W140 central lock problelm
 

I have a 95 S320 that won't lock the passenger's side front door when the central lock feature is activated on the driver's side with either the remote, a key, or the dash button. I can lock the passenger door manually from the inside by pushing down the knob . It will unlock using the key in the passenger door but not the dash button. Any thoughts as to why and how this is repaired?

Sorry, I don't understand what you wrote. If it won't lock then it would be unlocked all the time, so how can it unlock what is not locked?

Lately my '84 300SD T/D key(s) won't activate the central locking system, but on the passenger side it will lock tand open the front passenger door. I have oiled the lock through the escutcheon, and also the lock mechanism, but no joy!

Knowing that it has an electric door locking module, I thought it might be the relevant fuse, but my shop manual indicates that the designated fuse also operates the Hazard flasher, clock and radio, all of which work fine.

Any thoughts anyone?

Pump or leak
 

There might be a leak in the pneumatic tubing to the actuator, actuator in the door might leak or the pump is bad.

Does your vacuum pump, below the rear seat, work normally, i.e. when locking/unlocking run for few seconds, not more?

Check the tubing first for leaks and operation first by removing every tube from the pump manifold and sucking/pressurizing them individually.

marrku,

I am still shopping for a S320 ... do you have any advice on years to consider? Opinion seems to point towards more reliability in later years 1997-1999. Others have pointed out that earlier 140s had more "content," referring, I think, to "better" materials ... I haven't been able to discern what actually changed ...

Comments?

Thanks!

S320
 

Some typical faults have been rectified in later models, like aircon faults. W140 is not the most reliable car, it eats bushings and bearings for breakfast. Such complicated beast is not the cheapest to maintain, but your pride and joy when cruising the motorway.

Happy hunting.

Thanks ... give a choice, would you say there is any difference between a 97 and a 99 version?

I am aware of the earlier issues with evaporators, but sounds like later versions escaped this ...

TRANSLATION:
my 95 s320 will lock all the doors but the passenger side, but when locked manually (opening door, and pushing button i asume) the central lock will not unlock the door. but the key will (well, surprize surprize, isn't that what the key is for??)

what your problem is, is either electrical (electric solenoids (un)locking door)
or vacuum (vacuum cilinders (un)locking door)
check your wires (or vacuum hoses)

How many threads have we got going here?:confused:

Remote
 

Incidentally I run into this same feature today when my remote batteries run flat. I did open the drivers door with the key, but the passenger door did not unlock, neither by the key nor by the dash button. Unfortunately my wife was waiting outside so I did not have a chance to do any further research, just open the door by the handle.

Quick look at the User's Manual reveales that this is a feature: central locking for all doors works only with remote. Central locking/unlock only drivers door feature in remote can be enabled/disabled by pushing lock/unlock buttons of the remote simultaneously for 5 seconds.