Battery Isolation questions

[Trucker12]

I own a 2007 Silverado 2500 HD with the factory installed towing package. I want to charge my travel trailer battery while I am towing. As I understand it, all I need to do is pop a 40 amp fuse in the fuse box where the red plastic dummy fuse is located. Is this correct? Also is there already a battery isolator in the factory system or must that be added? Thanks in advanve for any information you may offer!

[Sillyoldman]

bump

[bighaas79]

There should already be a lead taped up under the hood by the fuse block from the factory. They were installed but never connected. They have an eyelet already on them to put over one of the battery studs under the cover of the fuse block. You will need to find a nut to secure it with however because they weren't supplied. That should make the terminal hot in your trailer connector.

[Trucker12]

Thanks for the reply, I had already found that information in the archives. Here`s the thing! I aint got no stinkin wire taped up, and I aint got no stinkin post. I DO have the 2007 Classic towing package. So I will pop a 40 amp fuse in the fuse box and see if I have power to the 12 volt wire. Also, I don`t know if the truck battery will be isolated from the trailer battery when the rig is parked. But once again thanks for trying to help me!

[Trucker12]

I put a 40 amp J-case fuse in the fuse box where the red plastic dummy fuse was located. That supplied power to the red wire in the trailer plug. There is power at the plug with the truck running and when the truck is turned off. This indicates to me that the truck battery is not isolated from the camper battery. So now I need to find a wire that is only hot when the truck ignition switch is on. I need that to wire up the battery isolator. Anyone know of an easy wire I can tap into for 12 volts when the ignition is turned on and dead when the ignition is off?