Temperature Gauge - 93/GMC 1500

[KornDogg]

I have a problem with my truck.  Seems that last night the temperature gauge quit working.  The sender was replaced, still no gauge.  When I turn the ignition to the start position, the gauge pegs out (as it has always done), this leads me to believe that the gauge itself is fine.  Tried shorting out the connector on the sender, no reaction from gauge.  Also checked for voltage and amperage at the connection at the sender, all is well.  Reset the computer, still no gauge.  When I disconnect the connector from the sensor, the "Service Engine Soon" light comes on.  Thermostat is operating fine.

 

I have no clue what this could be, I'm about to pull out my hair on this one.  Anyone run into this before?

 

Truck is a 1993 GMC 1/2 ton, 305/4L60E

[badhammer]

sounds like you are testing the wrong wires. the ones youare testing what color are they? the sender for the temp gauge is in the side of the left cylinder head between the front two spark plugs has a green wire going to it. when you unplug it the check engine light should not come on sounds like you are testing the temp sensor for the ECM in the truck that sensor has two wires a yellow and a black wire this is for fuel managment not the gauge.  

[KornDogg]

Thank You! Thank You! Thank You! Thank You! Thank You! Thank You!