84 SD 300, a number of electrical problems developed. It started with the speed o meter not working, then the fuel, oil presure, and temperature guage.And the off climate controll button stopped working. And to add to the problem, the starter sometimes will not work, until after a cooldown period, or until something is wiggled, just right.
The starter, I had tested against a new one, it is good. The instruments, I replaced with a salavaged one , and now all the instruments work. Except for the climate controll switch. I have another one, I hope is good. The starter, I need to check the nutrual switch on the transmission. I hear it click, but will not spin. Yesterday, I moved the shift lever a couple of times, and it worked.
During all the trouble shooting, looking for wires shorting out, I noticed the two rear, closest to the driver, silver relays get very hot,I mean real hot. while running the vechile. I aquired a number of used ones and have tried switching them out. The other two remain cool. If I am thinking clearly, this represents a short some place. The only thing that does not work, if these two relays are removed is seat adjustment and windows. Everything else still works.
The bonding wire is on the starter to transmission bolts, but I have not looked at the other end of it yet. Is there another bonding wire or grounding wire I migh be missing on this car ? Will the key synoliod cause a short to heat these relays while running, if it is bad?
is there a master relay on his car, as there are two black relays at the real of the fuse box? But they are not warming up. I suspect, looking at the fuse location chart in the fuse box, as it is not correct, this car has been rewired at some point, or the chart was changed, but it does not show the relays.
Electrical can be illusive, but obviously I am missing something, any information appriciated . Bill C
