Mercedes: 300e overload relay, electrical hookups, voltage spikes

Question
I just had a used transmission put into my 1990 300e,
When I picked it up the ABS light was on.
I worked with the transmission mech and we found out that the fuse blew on the overload relay, I replaced it and it seemed to work well for a day. When I started the car the next morning it blew again. The local Mercedes expert said to replace the relay it self they actually sell two of these units a month meaning that they go bad. The fuse held for another day and blew again. I have never experienced this problem for as long as I owned this car (5yrs). Obviously replacing the transmission has either shorted something or what. The transmission store says it can not be their problem that the transmission has no means of putting an electrical overload on the system.
Do you have any thoughts?

Answer
The Auto Break System is important for safety and you need to determine from where the issues is coming. The ABS system operates on top of your standard brake action, you just will not have anti skid capability.

There is most likely a short  or loose wire somewhere that is causing your troubles. I suspect that during the transmission install a wire was loosened. If you have a bad ground, it could be causing a high resistance short in the wiring that the Over Voltage Relay senses as a high Amp Short and the fuse blows. I would place the vehicle on a lift and take an opportunity to go over all the possible fittings.
Pay particular attention to the break calipers and the electrical hookups
The over load relay is just that and is protecting the electrical components from voltage spikes and surges. I would not tempt fate. If you keep challenging the the relay you may crash the computer, or worse.
Good Luck,and let us know what you find out.
Rob