Engine coolant temp sensor question

[panamarojo]

I was checking the voltage on the coolant temp sensor, the one that is connected to the ECU. Well when I apply the probs to the harness side, I hear a kinda like grinding noise coming from the ISC, only getting 2.5v which is below what the book says. If I unplug the ISC it doesnt make the noise when I test it. Ill have to see if the volts go up next time when I unplug the ISC. Is this normal or what is going on here? is the ISC shorted to the coolant temp sensor?

This is on a first gen by the way.

 

[mike420a]

Maybe a Short Circuit or the arness are damaged or bared, you can also test by cleaning the arness and the temperature sensor connector with carburetor cleaner spray, sometimes that solves the problem.