I am having trouble getting my temp gauge to work on the dash. I pulled the connector off of the sending unit located at rear of head on driver's side and I shorted the connector. The gauge responds immediately by jumping to max temp. I thought by doing this I had determined that the gauge and the wire where working properly and that the sensor must be bad. The guy I bought the jeep from said he had just replaced the sensor but I went ahead and replaced it again. I let the engine run for about 15 minutes and all the hoses felt pretty hot but I still get no response from the gauge. The jeep is a 88 and the motor is a 96. Are these sensors intended to only operate "idiot lights" or should they operate full range of temperatures on my gauge. I'm not sure what to try next short of replacing the sending unit for the third time??

 

Is this sending unit in any way tied in with another sensor (like the one on the thermostat housing). Could my gauge be bad even if it is responding when I short the connector wire?? I am getting desperate.

 

still can't get this working. any advice?

 

I just found out there is 2 different sensors you can buy and they look the same. One that will just operate an warning light and one that will operate a gauge (like in my photo).
I kept getting the wrong one from the parts store. The one I need for my gauge is part# 53005309. I hope this fixes it!

 

Finally it works! I hope this thread prevents a headache for someone someday because it sure gave me one. It seems like an easy mistake to make. I went to three different auto part stores and gave them my make and model and they never asked if I needed one that operated a warning light or one that operates a gauge. Now we know!