Patrice said:
I forgot to mention, the truck is charging fine at home on level 2. I’ve read that when the battery module fails, they can’t get a charge to work.
There’s nothing wrong with your truck. Cold temps and a low battery reduce the power to the motors.
Patrice said:
I forgot to mention, the truck is charging fine at home on level 2. I’ve read that when the battery module fails, they can’t get a charge to work.
I had a battery module fail once, and I got lots of warnings. Power dropped to around 20%, but I still made it to the dealership. It felt like driving a non-turbo 6-cylinder, and regen braking wasn’t as strong, but the regular brakes worked fine.
I think power reduces when the battery level drops below 50%. It’s happened to me, and I’ve wondered about it too. Does it really matter? Even when I pull out into traffic, I don’t need 100% power.
Vesper said:
I think power reduces when the battery level drops below 50%. It’s happened to me, and I’ve wondered about it too. Does it really matter? Even when I pull out into traffic, I don’t need 100% power.
If you get below 5% battery in the cold, you’ll definitely notice it! 
@Dane
I haven’t reached that low yet!
@Dane
I got down to 8% power at 5% charge in 20°F this morning. That was a bit scary on the highway going 75 mph.
This always happens in colder temperatures.
There was a post recently about a guy in Canada who left his truck outside at -40°F. He only had 22% power available, and with the heater on, his truck was using about 1% of the battery per mile. He got about 100 miles of range. It’s extreme, but he was charging with just a 110 plug.
@Murphy
I’d be dead if I had to deal with -40°F, truck or no truck.
Landry said:
@Murphy
I’d be dead if I had to deal with -40°F, truck or no truck.
I’m from Maine, so I’m used to negative temps. -40°F is crazy though. At -50°F, exposed skin freezes quickly. The funny part is the truck was only charging 1 mph with that 110 plug, trying to keep the battery warm.
Landry said:
@Murphy
I’d be dead if I had to deal with -40°F, truck or no truck.
Landry said:
@Murphy
I’d be dead if I had to deal with -40°F, truck or no truck.
I wouldn’t even know the power state of my truck in that cold. I’d be dead. 
This happens in the cold, no matter how much charge is left in the truck if it hasn’t been plugged in.
It’s just the truck protecting itself from the cold. Once you plug it in and charge at home, it’ll go back to 100%. But if it’s cold outside, the power will drop from 100%. This is normal and nothing to worry about.
Mine does the same thing when it’s cold. No need to worry.
It could be an issue with the HV (high-voltage) battery management system or software. If you’ve noticed the issue continuing, you might want to take it to a service center. Otherwise, it’s probably just cold weather and battery voltage fluctuations.
I’ve seen some recent software updates that might be related to cold weather battery management. It should return to normal once the truck warms up.