Nissan Repair: coolant temp sensor, coolant temp, hardboy

Question
hi, i have a 91 nissan hardboy pickup recently my MIL light came on, so i checked the code and it turned out to be the ECT sensor so i changed it the light went off for ten minutes or so then came directly back on check the code again same thing, so i cleaned the terminals at the connector and still same code???? next im thinking maybe a ground what do you think? also where is the ground located for the ECT (coolant temp sensor) circuit on this vehicle?

Answer
Tyler,

If yours is a one wire the temperature sensor is the ground.  Check the engine ground and make sure the computer is in its proper location and that the ground on it is good too.  You might have a bad connector.  You can bridge the connector to verify and see what the gauge is doing when you ground it.