My 1989 300CE has non-functioning tachometer, clock when ignition is on, and oil pressure. I've replaced all the fuses in the fuse box with new ones, as a first step before taking the cluster out.

The first thing I tried was swapping a working cluster from my 1989 300E into the car to test and all the gauges started working. However, I smelled a burning smell and immediately pulled the cluster out. I put the 300E gauge back into its original location and thankfully it is still working. (edit: I think the oil pressure gauge is busted now. It is now pegged at 3 instead of fluctuating around)

I've taken both clusters apart trying to find any burnt traces that need to be reattached with a wire and I discovered this:



Does anyone know what that trace is or what it does? It looks like the left turn signal ground wire if I'm not mistaken. Where does the trace go to? Will fixing this solve my problems with Oil/Tach/Clock ?