w210 drivers door locking issue
 

Hi all.
i am a first timer to this site & also I recently purchased a 1998 w210.

I have inherited a problem with the drivers drivers door only locking with the remote when it’s pointed at the infrared door sensor. It does not lock when the car is in motion or if we use the dash mounted central lock/unlock button.

There seems to be no restriction on the lock e as I already disconnected it from under the rear seat, suctioned & blowed into it with little effort getting a response every time.

i observed it moves very slight when using the central lock button, it seems to have insufficient air or vacuum to move it. If the doors are locked, I would have to press the button several times for it to progressively unlock. It doesn’t ever lock though

can anyone advise me on this

I guess I’m on my own here then..

You'll get more responses if you post in the W210 sub-forum. Plus not all of us spend all of our time on here, we have lives to live.

Best way to check is to hook it up to a STAR diagnostics system and run through the test and actuations menu for the Pneumatic System Equipment Control Module. The vacuum pump has multiple solenoids in it to push/pull pressure/vacuum to each vacuum line. So, is it the vacuum pump solenoid failing or is it a CANBUS issue?

A quick test to see if it is the vacuum pump solenoid for the driver's door is working properly is to go under the back seat and swap the driver's door vacuum line with another door's vacuum line. If the driver's door suddenly begins working and the other door does not, you've found your problem in the vacuum pump. If this doesn't do it, I recommend STAR diagnostic. Attachment is for the W220 PSE but it is an enlightening document.

https://cimg2.ibsrv.net/gimg/www.mbw...4cd479a0ab.png
https://cimg3.ibsrv.net/gimg/www.mbw...094ce674ec.jpg

Wonderful bit of information.
I have tried the vacuum pump reset after reading through your info, but it had no effect on this issue.

The vacuum works very powerful on all doors when locking or unlocking with the car off & standing outside. The only malfunction is the auto lock feature when moving or the dash lock button has little to no effect on the drivers door for some odd reason. Which means that door always remains unlocked at all times unless it’s locked from outside with remote or key.

I appreciate your information very much though. It has helped me understand the system a bit more. I’ll try to find the w210 forum, may take me a while being new to this and all.

much thanks again