MIL was on this morning....-12*C.....block heater was plugged in for 4 hours prior to starting. Got trouble code P0514...."Battery Temp sensor Performance/Rationality."
Read on a another forum that this code appears quite frequently when plugging the truck in overnight.
Anyone on here ever had this scenario.....and what was done to eliminate the problem??? Flash???....

Check with the dealer to see if there is a new calibration available for your truck. There isn't anything wrong, the diagnostic is most likely just flipping out when coolant temperature doesn't match the battery temperature after a few hours with the engine off.

Seems like there was a TSB for that fault code and some others corrected with a ECM update. I however would check your battery cable connections for corrosion. The 03 and up trucks use the drivers side battery for voltage sense for the PCM to regulate charging. The problem occurs when the charge wire from the alternator goes to the passenger side + battery terminal first. When the connection to the drivers side battery is bad, the drivers side battery will not get charged. The PCM will then turn the alternator on full-tilt and cook the passenger side batt.

Code hasn't come back, but I'll go see the dealer to see if there's a flash for the PCM or a TSB.
The battery cables are clean and no crap around the battery trays.
I'll let you know what the dealer does.

The Dealer flashed the PCM with the latest update available.....should actually take care of a few other issues as well that could pop up.
Cost was a bonus....NO CHARGE !!!