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Thought I'd disconnect the seatbelt warning switch...

So today I dug around under the driver's seat of my '79 300TD and found what I assumed to be the connection for the switch for the buzzer that sounds when the seatbelt isn't engaged. I disconnected the "harness" (all two wires of it), and hallelujah, my seatbelt buzzer stopped sounding when I turned the key to start the glow plugs.

Then I noticed that the front passenger window no longer worked. It had been working earlier in the day. All other windows work fine from the center console switches.

Are these systems in any way related? All of the fuses are intact (despite me coming to realize that I might just as well replace them all), so that's not the problem. I thought it very odd that disconnecting the harness caused that problem to manifest, so I plugged the harness back together, and still no window operation (but the buzzer is back). Sigh.

Since I still need to diagnose the disfunctional vacuum I figure tomorrow is as good a day as any to take the door panel off, but are there any particular points of failure to look at that anyone can recommend?

thanks,

-tom!

Reply to
Tom Plunket
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Oh, and poking around in the fusebox, I see fuse 'd' is for the roof, but mine's got a manual roof. Does this mean, then, that this fuse is unconnected to anything? Perhaps I can take it over for own nefarious needs (aka power for the GPS).

Oh yeah and I just rememebered, I don't see anywhere for the lighter socket to connect to power. As, there aren't any obvious terminals on the ashtray assembly, and there are no wires hanging down that would appear to connect to this unit... Always curious, though!

thx!

-tom!

Reply to
Tom Plunket

Looking at this more closely, I see that the lighter connections are sliding connections along the side of the ashtray. Very cunning!

-tom!

Reply to
Tom Plunket

I took this apart today, and yes indeed coincidentally the switch went bad at the exact same time that I disconnected the seatbelt warning buzzer switch.

Tested the switch, and it 'down' doesn't make contact with the mains. It doesn't appear that this part is serviceable (am I missing something?), so I'll order another one in the morning for $30.

While it was all apart, it really looked like someone spilled something down in there like coffee or something. Anything specific that'd be ok to spray on the connectors to help me clean 'em up? The center console itself cleaned up nice with just warm water.

thanks,

-tom!

Reply to
Tom Plunket

There is an electrical contact cleaner spray (no certain what is in it) that can be purchased at radio shack or the like. I think the brand I have in my shop is CRC. I use it for all sorts of electrical contact cleaning. Back in the day, I used to use a dollar bill to clean reed and mercury wetted relay contacts on computer systems :)

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me

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