Hey all,
Coolant temp gauge always reads 100 (the lowest reading), and after looking through past threads, I found the sensor for it on the driver side cylinder head, but there's no wiring coming out of it. Can anyone tell me what the setup is supposed to be?

1989 K5 Blazer, 350 V8 engine, 5.7L. Had gauge cluster replaced when I bought it, but still no temp reading.

 

Look for a single wire with a rectangular, black terminal that slides onto the pin on the sensor. It may have been cut off

 

I believe the wire will be green.

 

Thank you for the tips! Found the wire (I think) but still no reading on the gauge. Time to switch out the sensor? Do these commonly go out?

 

Try grounding the wire momentarily and see if the gauge goes to max. If it doesn't move, the problem is not the sensor.

 

I was gonna say it doesnt look like theres good contact, that old wire could be corroded under that tape, sensor could be bad, but I would check it as tom said.

 

Thanks so much guys! Drove for a bit longer and the temp picked up, so I think it's all good!

 

Still give the pin of the sensor a brush with a steel brush and clean the contacts.
The resistance on the connector(s) makes for wrong readings.