I have a 2007 Chevy Tahoe. I recently had a frost plug installed because 1) I live in MN 2) it sits outside when I go up to the cabin on weekends. After I use the frost plug overnight the DIC message displays "Engine Hot A/C Turned Off" however the temp gauge doesn't appear to be working. The engine fan runs constantly. I can't imagine the engine could be hot. It sat outside all night with temps below freezing. I can drive it but don't like to when it's doing this. The message displays usually for about 24 hours. I let it sit overnight without plugging it in and message goes away, everything seems back to normal. For now I'm just not going to use frost plug. Any ideas what might be causing this or anyone else experienced same issue?

Thanks in advance.

 

Welcome to the forum.

By "frost plug", I assume you mean a block heater in place of one of the freeze plugs. Since so much of this truck is computer controlled, I'd go back to the folks that installed it and ask them about it. Sounds like they did something to the temp. sensor circuitry.

Does the temp. gauge work after the engine is running?

 

Yup, block heater. The temp gauge does work after the message goes away. I asked the person who installed it who has been a mechanic for 30 years and a good friend. He seems to be a bit perplexed so I thought I'd reach out on the internet assuming someone else may have come across this. I guess the heating element on the block heater may be getting too hot and causing the T-Stat to stay open or something?? Not sure.....

 

I would too suspect its getting too hot and the ECM is confused by the heat when everything else is telling it its cold....
I'd consider a thermostat for the block heater or a timer to cycle it every hour or two...
If you feel the block heater is needed you should also consider a battery blanket or trickle charger to keep the battery up to snuff, this is probably more important then the block heater...

 

I have a similar problem as first postr (DIC message displays "Engine Hot A/C Turned Off to protect Engine") I have a Chevy Uplander 2008 I have not done any work to it. So same situation exept i have not done any work to the van.

Can anyone help?

 

Wow is it been this long, and no one has made a post with any new ideas? well I did take the car to the dealer and the changed the thermostat, the problem went away for a while, but now its back and now I have a check engine light on. Any ideas guys? thx

 

I have same problem engine hot a/c turned off. Been having trouble with it starting ,starts second try every time tho. But now that a/c is turned off , it starts decent . Changed too many sensors to try and fix the starting issue until the check engine lite turned off , but no luck .