On my '91 300CE, I have tested the convenience control module (under the back seat, behind the driver), and it appears I have a a faulty lock switch. Both of the front doors failed the ohms test (trunk passed)...not sure what this means - or how likely it is that both front door switches are bad.

Anyway, I have pulled the driver's side lock and I see one white wire connected to the lock cylinder - what does this wire activate? Alarm system? Convenience features? How do I test this 'lock switch'?

My alarm works fine, convenience features do not and I've had trouble getting my central door locking to work as well.

ryan

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RG Newell

1984 300D
1972 250
1986 560SL
1991 300CE

1.Do you have an aftermarket (Non Mercedes) alarm?
2.Replace Fuses "A" and "C"
(Notice I said Replace,Not Check...You don't need any more grief.)
3.Ain't No WHITE wire showing in the ETM portion of the FSM for the '90 or '91
300CE.[What's commonly called the "Wiring Diagram"].
There is However a RED wire with a white stripe.
There is also a YELLOW Vacuum Hard Plastic line.
There is a BROWN wire.
There is a BLUE wire.(This is the one that would go to the "Comfort Control")

4.Testing Accomplished with a Multimeter and Wiring Diagram[Spelled FSM]
And an understanding of German Electrons
(They're more "Fussy" [Correct]than American Electrons)
[I know, I know you have an American Battery...How can the Electrons be German?
Apparently Electron's nationality is determined by the Wiring.]

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'84 300SD sold
124.128

1) No
2)Already did
3) I know - I have reviewed the wiring diagrams for what seems like hours and I can not find the wire that I am talking about either. If you read thru FSM 82-0995 Troubleshooting table convenience control power windows/tilting/sliding roof (ECE), Test step #16, you will see reference to lock switch (S86/1 - driver's side, and S87/1 - passenger side). I can't find these anywhere on any of the diagrams. So, I pulled the lock cylinder and there is a white wire/switch connected to the lock cylinder. This is not the electrical connection at the lock actuator...

However...I may have fixed my convenience/comfort system by replacing the voltage regulator. On what I thought was a separate problem, I was noticing that the battery wasn't fully charging - changing out the VR got me over 14v at idle - and I think it may have fixed this problem.

ryan

__________________
RG Newell

1984 300D
1972 250
1986 560SL
1991 300CE

(BUT ,Not really!) How "OFF" Voltages [and you'd be surprised , Amperage s]
can throw ANY component into fits that you think cannot be explained?

I still want to know what that damn WHITE wire is/goes to...If you find out
please P.M. me.

__________________
'84 300SD sold
124.128