I am installing an RV Battery and have installed a relay so it will charge when the truck is running and disconect as soon as the truck is off, The problem is i can't find a wire that has 12v only when the ignition is on. I need a wire that only has 12v with igniton, to engage the relay to connect the batteries. I thought the fuse box would have something but i didn't find it ? (2006 Quad 4x4) Any help would be appreciated

 

The easiest wire to use is usually the cigarette lighter, check yours first for no power with the key off.

 

I believe fuse # 31 or 32 has ignition on only power.