Old thread but I'll add my 2 cents. Front left window wouldn't go up on my daughter's 84 126. Sprayed a bunch of electrical cleaner in the cracks around the edges of the switch, let it sit for a couple of minutes and it worked. So I now have this idea that rather than disassembling the switch it might work to drill a hole thru the plastic and spray cleaner down inside on the contacts. May try it.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

This is certainly worth a try; especially if you are not at Home.

It depends on the issue inside. If there is some junk inside or perhaps light burning of the Contacts the Spray might work.
Drilling a hole in the Switch also allows an entrance for more Junk so there could be a trade off there.

The Switch Contacts on Mine seemed burned beyond what some contact cleaner could be expected to do and I scraped them with a Pocket Knife and that was 3-4 years ago. The only issue I had was that I only did the Diver side Switch and ended up having to pull the others about 1 month later.

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84 300D, 82 Volvo 244Gl Diesel

Can someone tell me or point me in the direction of how to get to the switch I have a 1984 300td and the passengers window did this to me yesterday