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Mercedes 2001 E320 keyless system malfunction

Keyless lock system does not open doors or trunk. Vacuum pump working, changes air flow from dash to floor, to defrost, etc. All electrical based systems work fine, windows raise, lower, sunroof opens closes when keyless is activated. Door locks and trunk are vacuum initiated when keyless is used or on dash buttons are pushed, but the control device that causes the vacuum controller to activate is not firing. Where is the central controller located and what is it called?

Are you talking about your remote on your keychain not working? Have you tried changing the battery?

Remote on keychain works fine, battery new. When I push unlock button, lights flash as they should, but the doors do not unlock. The locks are actuated by the vacuum pump system, but whatever electrical that causes that to happen is not doing it’s job. There are three fuse panels on this car, checked all fuses in all three, no blown fuses.

Sounds like one of the wires from your vacuum pump isn’t grounded properly.

Perhaps, but vacuum pump is working all other systems it powers, ie the air flow on the air conditioner changes from dash to floor to defrost when those buttons are pushed. It seems to me that there is a vacuum controll valve somewhere that when unlock is pushed on the keychain remote that directs the vacuum to lock or unlock the doors. When it was working correctly I could hear the valve change state and the door would unlock. I’m trying to identify where this potential valve is located and what it’s called.

That’s right. It can’t be that because it still works manually. huh, your guess is as good as mine, but it seems your on the right track.

Thanks for your input. Perhaps someone has experience with this issue and will offer information.