Adding isolator relay under hood of 2017 Chevy 2500 diesel

[Lafayettemo]

Can someone tell where under the hood I can find the B+ wire that runs back to the trailer plug on a 2017 Silverado 2500 Duramax? The B+ terminal is currently on always at the plug and needs to be off when the ignition is off to avoid running the truck batteries down. Additionally, is there a best place to connect to an ignition on + wire to power the isolator solenoid? Thank you!

[cfowler55]

Usually GM puts it on a post on the end of the under hood fuse box. Remove the cover to expose. I will try to remember to check on my shop software Monday to confirm.

[twinboat]

You can use this, and not need an ignition source.

It will only close if the trailer is connected and the PU truck is running.

It senses voltage on both sides and only connects if charging ( 13.2 ) volts are present on one side or the other.

[Lafayettemo]

"...use this..." .Was there an attachment intended? Thanks

[twinboat]

Whoops.

[mobilemike]

Its called a VSR or voltage sensing relay