Thanks. I don't think so but I'm going to do it anyway since all my bright ideas haven't worked. I'll try anything and it's not only cheap, it's easy.

I've previously carefully cleaned the grounding connectors by taking an eraser to them. I'd guess they are much the same as the W123's. There was a bit of corrosion on them. I checked continuity all the way from the grounding pin (#1) on the 15 pin main connector and into spots on the printed circuit board from the post connector on the board and everything checked A-OK so I don't think it's a ground issue.

Any thoughts on the warning lights and ignition switch?