Temp Sensor Relay?

[Fozzy]

This kind of freaked me out. 2008 Silverado V6. right at the magic 50K mark Driving to OKC today and minding my own business when I notice a message on the message center. ENGINE HOT A/C NOT OPERATING (I think that's what it said). I quickly scanned the temp gauge and it was dead.. (sitting on 160). There was no alert, no engine lights.. just the warning on the message center..

 

I pulled over and shut off the truck and checked it out.. nothing out of the ordinary, nothing changed and it definitely was not hot. I restarted the truck and the message returned.. same thing.. I decided since there were no low fluids and the truck was acting normal to run it till it either corrected itself or melted... I figured that it was the coolant temp sensor. The A/C (just like the message said) was inoperative.. the light would blink but it would not turn on.

 

I looked for the temp sensor in all the normal places other cars and trucks have them.. couldn't find it. On the way home, I was sitting at a red light and noticed that the temp was back to normal (or around the 210 mark).. check the A/C and lo and behold, everything is fine now. Is there some relay that is doing this or a temp sensor or gremlins?

[alvocado]

The coolant temp sensor is threaded into the drivers side cylinder head on my '02 Yukon. Check your connection and worse, case, the sensors are not expensive to replace.

[Fozzy]

The coolant temp sensor is threaded into the drivers side cylinder head on my '02 Yukon. Check your connection and worse, case, the sensors are not expensive to replace.

 

I've been doing lots of research on this.. I found the exact problem from several other people on this truck and replacing the coolant temp sensor nor replacing the thermostat fix this. One guy pulled the battery cable every time it happened to reset this.. but it seems like an electronic bugaboo.. I hate those!!