Is a battery isolation device standard?

Do new trucks have this device built in? How can I tell on 2023 sr5?

When parked, wish to isolate camper or cargo trailer battery from truck battery. When traveling wish to keep connection for charging from alternator.

Sometimes I forget to unplug or replug trailer from/to 7 pin port on truck.

 

What he said

 

Your talking battery charge pin on the trailer plug?
If so yes on the factory trailer plug that circuit is turned off when the key is off.

 

I would think this would be the case. OP, maybe just put a test light on it, and see.

 

Thanks all. My 2012 build, 12v auxiliary to camper is always on... but I hardwired everything myself.
When I get delivery of the 2023 will test output, good advice.
A future mod to add DC to DC converter for my camper battery charging will probably require adding the isolator and running 8awg the length of the truck.

 

On both 2nd and 3rd gens the Batt + on the factory trailer plug wiring is powered off when the key is turned off.
It's powered by the BATT CHG Relay which is turned on by the IG1 No 2 Fuse (hot in Run & Start).

If it's an added on plug then you would have to test it with a test light to see if it turns off with the key or not.

 

yes, there's a 'side car' box on the underhood fuse block. within that contains a relays, of which one defaults to not connecting trailer power to vehicle power unless the vehicle is running.

on my truck, i altered that relay to stay closed so as to provide power to my bed light switch

 

So why not install a disco switch on the trailer?

I installed one on mine, primarily because I don't want a few hundred bucks worth of batteries running down every time it's not in use. Same principle applies when parked and connected overnight. Just flip the switch, and the systems wont siphon off of either battery, nor would the batteries siphon off of each other, if you do it correctly.

 

Helpful info, thanks all.