Problem now?

Ok, I have managed to swap trannies, and all works great, except now the temp gauge does not work. Weird but this is the only one that has an issue, which means that the sender or wiring is bad and therfore won't trigger the fan to come on. It was working before we took the tranny out and swapped, and all the wires are hooked up and everything else is fine. I found a splice in the wire and cleaned that up, but still nothing. How can I test the gauge? How to test the sending unit? I assume if it is hot the unit will show a closed circuit? Ohm test shows closed and the engine was very warm to the touch, burning like a normal running engine is. I guess the test of the unit for an open circuit would need to be done tomorrow when it is cold. But how to test the gauge? I tried the suggestions in the manual I have (Chilton) and nothing produced any results of any kind. When one wire is checked I get about 4 volts of power on it, and 0 on the other, should be normal right? Or should it be 12 volts on the one and 0 on the other? Anyway, with summer coming and hot days here in the west this weekend, I would rather not push it, but I can hardwire the fan in to be on whenever the car is running, or by switch. But suggestions if you have any!

Thanks!
Jeff

Fixed that one, just a loose wire.