W116, Body and Interior Specific Aid

Missing Vac Switch in ALDA line.

I have a 1979 W116 300SD, chassis has 334k miles and rebuilt engine around 100k. When I purchased the car, the vac switch that attaches to the firewall that helps control the ALDA valve is missing. I have read various articles describing the pro and cons. I am afraid to 'step' on it in fear of what may happen. Should I replace the switch? Or what would you do?

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1985 w126 300sd cental locking system failure to lock

I have posted this question on a few other Mercedes Forums with no assistance. So...I have paid the 30 bucks for hopefully some light to be shed.

I have a strange problem with my central locks.

The problem I am having is that locking any controlling (driver passenger trunk)lock will cause all locks to unlock but it is impossible to lock the doors. I obviously have no leaks.

What I have so far.
I have run the pump on the bench and if I ground any of the 3 pins the pump pulls untill the vac switch makes. Then if I apply 12v to a pin the pump pushes until the press switch makes. This seems to make sense. Keep in mind I did not test the pump with a constant 12v on any pins and I will try that later today.

I also tested the wiring in the car and all is correct.

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