I have the starter relay out, I’ve measured all terminal voltages where the relay plugs into with the ignition on but I am getting an interesting voltage of 3.5v at terminal 85 which is on the switching side (I’ve attached a photo of a drawing for easy reference). I assume this is suppose to be ground and is shorting to power but maybe I’m missing something in the electrical diagrams as the relay works fine although vehicle won’t crank. Also terminal 30 goes no where which is why there’s no measurement.
Any one with experience with the electrical systems of the g wagon would be greatly appreciated.
I have the starter relay out, I’ve measured all terminal voltages where the relay plugs into with the ignition on but I am getting an interesting voltage of 3.5v at terminal 85 which is on the switching side (I’ve attached a photo of a drawing for easy reference). I assume this is suppose to be ground and is shorting to power but maybe I’m missing something in the electrical diagrams as the relay works fine although vehicle won’t crank. Also terminal 30 goes no where which is why there’s no measurement.
Any one with experience with the electrical systems of the g wagon would be greatly appreciated.
Measuring the relay socket voltages with the relay removed and not cranking isn't especially meaningful. The 3.5 volt terminal measurement should be ground (0 volts) while cranking, but otherwise floats (hence the odd voltage). The 24 volt terminal should become 0 volts while cranking. If you want meaningful measurements, you need to make them with the relay installed and while cranking.
Measuring the relay socket voltages with the relay removed and not cranking isn't especially meaningful. The 3.5 volt terminal measurement should be ground (0 volts) while cranking, but otherwise floats (hence the odd voltage). The 24 volt terminal should become 0 volts while cranking. If you want meaningful measurements, you need to make them with the relay installed and while cranking.
What this guy said. Thats feedback voltage out of the M.E. Plug the relay in and slip a back probe pin underneath on that terminal and you should read 12v then once activated it should drop to 0v
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