1991 Ranger temperature gauge not working

lacrossesoaked

Temperature gauge has stopped working. trying to trace where it is connected under the hood. Is the gauge connected to a sensor with the single wire at the thermostat (the one which just pulls off) or is it connected via the larger multi-clip bundle below the thermostat? If I locate the correct wire, is there a way I put a charge on it to see if the temperature gauge moves so that I would know if I had a bad gauge or a bad sensor? Thank you.

bolivar

I 'think' the temp guage wire is a single wire. The two wire, with a black and yellow twisted together, is a senor that tells the computer when the coolant temp is 'warm' and helps the computer put the system into 'closed loop' condition.

I 'think' you can pull the wire and ground it and the guage should read full range.

I 'think' the sensor is a variable resistor, changing with temperature increase. Starting cold, pull the wire, check the resistance (ohms) and keep checking it when it warms up. The resistance should change. Not sure if it should increase or decrease. But if I am right above, if grounding goes full range, it should probably decrease as temp increases.

Since I'm not sure about any of the above, they might all be wrong. But just fool around with an ohm meter, what can it hurt.

Or, just replace the sensor.

lacrossesoaked

Thanks for the info.