Opelotus

During several projects I was working on last winter I managed to break off one of the terminals on the rear defroster upper grid, driver side (ground side I believe). Now that the weather is cold and the car is being driven daily, it would be nice if the defroster/defogger worked as the rear window likes to fog up. Has anyone had luck repairing these terminals? It appears as if they were lightly soldered onto the glass at the factory but I am afraid of cracking the glass attempting to resolder it. I have also heard stories about people attempting to repair similar defroster terminals (not on 928s) and had the glass crack when they activated the circuit (thought is that the repaired connection had too much resistance, heated up and created a hot spot on the glass).
Any ideas?

Also, should the rest of the system still work even if one defroster grid is not connected? The heated mirrors do not seem to be working either (no voltage at connector in mirror with the defogger energized. Not sure if it has something to do with the open defroster circuit.

And correct me if I am wrong, but according to the wiring diagram it looks like the heated windshield spray jets are on anytime the key is on?

US '84 928S

Opelotus

After studying the wiring diagram and drawing out the circuit on paper, it appears that only defrost mode will work with the broken grid connector (only one grid will power up though, in this mode they are wired in parallel) and the mirrors should defrost as well. Defog mode requires the grids to work in series, so with a broken ground connector it will not power up (mirrors don't power on in this mode).

So the question remains, can the connector to the window grid be repaired?