Peter M

I have checked the forums and used the search bar but cant find anything on this subject so yet a new thread on an old problem :P
1995 Camaro V8 5.7
I just replaced the radiator and thermostat (new cap as well) now my coolant fan wont turn on.
I checked the relays (including the ac) all are working, jumped the fans to the battery and both work fine so I pulled the temp sensor and a good thing I did! the old one was corroded and the pigtail was disintegrating. I bought a new one from the dealership. The old sensor only had 1 wire(black) the new sensor has 2 wires (pigtail purchased with sensor, black & yellow wires) the temp gauge on the dash did not work until I touched the yellow wire to the body
My question is am I correct assuming the yellow wire is a ground and should be treated as such and does this influence the coolant fans(on/off)
Ok one more question... Is there anything else I may not be thinking of?
Thanx in advance