My W201 has developed an unusual door lock anomaly: I always lock the car when I leave it on the street in front of my house. After several days, I'll notice that the locks are all up and the car is completely unlocked. Here's the weird part: if I take the key and turn it in the driver door, all the locks will pop down, meaning that there is still plenty of vacuum in the system! This is, of course, without starting the car to replenish the vacuum.

This is very different from my W123, which has a slow slow leak in the vacuum system: on the W123 the vacuum will be gone after a couple days, and when you turn the key in the driver door nothing happens on the other doors. They only come up after I start the car (to the annoyance of my passengers).

Any ideas? It seems like this is a problem in one of the front door lock assemblies: it lets go by spring force or something, and all the others follow?

Kurt

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- '79 240D - engine swap complete! Engine broken in! 28-31 mpg! Lovin' the ride!
- '86 190D (W201-126) - 2.5 NA engine, 5 speed, cloth interior, manual climate controls, 33-34 mpg (sold to forum member).

W201 does not work with vacuum reservoir like the W123. It has a vacuum pump, either in the trunk or under the back seat to pull/push to lock/unlock the car. I believe you have an electrical problem at the driver door actuator or at the vacuum pump. The car will always has vacuum as it is on demand.

It is unlikely the switch has problem as there is quite a bit of travel inside the switch. I would suspect you have a faulty pump which comes on to pressurize the line to open all doors.

Good luck.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Dang, this is going to be fun to figure out! Thanks for the advice, ah-kay.

Kurt

__________________
- '79 240D - engine swap complete! Engine broken in! 28-31 mpg! Lovin' the ride!
- '86 190D (W201-126) - 2.5 NA engine, 5 speed, cloth interior, manual climate controls, 33-34 mpg (sold to forum member).

I'd swap in a known good central locking pump and see if that fixes it.

Sixto
87 300D^2