Whoa, just the first days of Autumn and its already -40F according to the overhead, YIKES!!!. And I was caught without a coat.....

Today's temp reading is more normal. This is probably an intermittent open temp sensor circuit (or failing sensor), right?

 

I had the same problem as you and there is a TSB for this.

http://dodgeram.info/tsb/2006/08-026-06.htm

Get'er fixed!

 

Thanks, I saw that TSB, but the display stayed at -40 for an hour. When I started up this morning it was back to normal....

 

Get the TSB done, that is the problem. Mine has done it also and never moved until i restarted the truck.

 

I have always disconnected my neg battery cables for various little problems. This one, a time when my dome lights stayed on too long after I locked the truck, once when they went out too quick etc... Disconnected for about 15 minutes and never had the problem again!

 

It's a intermittent thing and can only be fixed if you have the TSB done.