Battery positive terminal wiring

[Joef]

GMC 2019 Sierra 1500 Denali, Can someone tell me what the small wire on the battery positive terminal feeds?

I flat tow my truck and have a relay installed to disconnect the battery positive power and need to know if the little one needs to be disconnected also.

 

Thanks

 

 

[garyo]

This may be the reason that GM says to remove the - negative terminal before you flat tow.