Parents bought 2008 bighorn 3670RL and Seller kept battery.

[TeacherSupreme]

Searched, no help. 4 cables red/black together and red/white together. How to connect?

 

[Roller4tan]

Red Positive/ White to ground. Red from 12v breaker row/ WHITE attached to frame ground. Follow the other red and black wires to see where they come from. Black is an automotive ground, white is usually used in rv's for ground.

 

[wdk450]

Most likely the top two big cables are the original (factory) battery system hookup cables. The lower 2 cables most likely go into the front compartment where more batteries could be connected to the main battery in paralell for additional current for big 12 volt jobs like front landing gear and hydraulic slideouts. BE SURE YOU KNOW WHERE EVERY CABLE GOES AND WHAT IT DOES BEFORE YOU MAKE ANY "NEW" CONNECTIONS!!! If in doubt get a mobile RV servicer involved. The current from an automotive battery short is enough to weld metal with, send melted metal flying towards your body, and possibly cause an explosion of the acid filled battery shooting acid onto you!!!