I can't stress this enough especially now with the colder temps. If you are having issues with your APU starting please let me know right away so we can get it into a Carrier Dealership to have the problem resolved. I've reached out to the Dealership here in Toledo about the not starting issue and they have said they have had several having issues with glow plugs going out. With the temps dropping the way they have been the APU needs the Glow Plugs to be working properly or they won't start. An APU not starting means when the voltage drops the battery minder feature that starts the APU won't work. The cold also plays hell on Battery life, even with the upgraded AGM batteries they still need to be charged when voltage drops to extend their life. Don't always trust the APU battery minder feature. Please keep an eye on the voltage from the display. If you are getting conflicting voltage reading from the truck, inverter display , and the carrier display those displays will have to be calibrated to match the truck. I really don't want any of you to be with out power especially in these cold temps.