Some control units will sound an alarm if you turn the ignition on with EHU attached but beware:
Some use the 12V from the charger to sense if mains is present so will not work if you've turned the charger off because you've installed Lithium.
It would be easy to build a warning device and connect it to the back of the fridge (where D+ and mains connections are conveniently found together).
Some use the 12V from the charger to sense if mains is present so will not work if you've turned the charger off because you've installed Lithium.
It would be easy to build a warning device and connect it to the back of the fridge (where D+ and mains connections are conveniently found together).