anybody has any idea how to fix the rear window's defrost line of my 79 300SD? it's been raining crazy here in CA and without the defrost line working, my rear window is fogged up all the time.
thanks for any good advice.

If it is the resistive lines (on the window) themselves that are cracked, find the cracks (either visually or with an ohm meter). You can either buy a pen at any local parts store (e.g., Pep guys, Autohome ) or buy a pack of juicyfruit (or any other flat wrigley's gum), chew the gum but do not throw away the silver wrap; instead, these wraps can be separated into a very thin (!) alu foil and the paper that this foil is resting on (takes some time to figure it out). you can rub small pieces of the foil onto the cracks so the lines are connected again... (Clean the window first.)

Hope this helps

Good idea but, the lines on my W126 at least are inside the glass. If the W116 is the same way I would sudjest finding a used window.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

My '79 300SD has wires IN the glass, not a grid ON the glass...........there is a relay that controls power to that.....is it working at all. I have same problem but not have managed to figure it out yet.

Keep in mind the 79 300SD is a W116 chassis

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Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
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