Coolers and battery life

It will knock down the batt. over a long wk. end but not over/night, a half bag of ice inside ziplock bag with it unplugged will keep food good in my same cooler if its out of sun and not sitting on hot floor of truck?

 

As long as you have decent batteries 12 hrs won't be a problem.

 

should have a battery protection on the truck i know mine does.Will cut the power when gets below cranking amps something like that. check your owners manual then the truck

 

I think every truck has a low voltage shut down these days. You're electrical circuit will shut down before the truck won't start.

 

If you're reading 13 volts after 14 hours. I'd be having them batteries looked at.

Full charge is 12.6 volts. A brand new battery in good condition will read 12.7 volts after stabilizing on engine shutdown.

Batteries that read 13 volts and stay there. Aren't soaking in the full charge from top to bottom. And to read that after 14 hours. With fridge useage.

 

Probably read them with a voltmeter which will read higher. He needs the meter that will add a load to give a more stable reading.