Thanks to Pucci for letting me know how to post pics!

This is the easy way to measure the ECM temp sensor, and will also verify that wires from this harness connector to the sensor are good.

My truck is an 88 Troop... I don't know if the wire colors or connector location will be the same on your rig. This connector is the larger of the two on the bracket on the passenger side fender well, right behind the battery.

These two wires, Black and Green/Yellow




Check cold first, use the temp/ohms chart that's been posted previously in this thread. Put a thermometer in the radiator, or use an infrared thermometer. (the radiator may be a few degrees cooler than the engine at this point...) Put the cap back on, plug the connector back in, and run the truck till it gets up to temp. Stop the truck, pull the connector and hook up your ohmmeter. You should read around 200-400 ohms. Check the meter from time to time as the engine cools. The resistance should slowly climb back to the first cold reading as the engine cools off.

C/YA!
JB