battery cables

Thanks for all the replys but I had to retire for the night, I forget this goes all across the country.
I have used the wrong word to explain my problem by saying "extra wire"it isn't an extra wire its just I think it got placed on the wrong battery by mistake and thats causing my electrical problems. Like the slide not going in or out the levelers not going up and down. With my slide out I couldn't move the coach. The mechanic came out to me yesterday and jumped the slide motor under the coach and got it to move back in, now I'm recharging my motor battery and this am will be able to drive it down to him for tracing it out and repairing the problem I hope. Can't figure out why a brand new motor battery would discharge with a battery charger hooked to my coach battery and a land line hooked to the coach. I just wanted to see a picture of the proper wiring to each battery as a guide line for him "mechanic" to make it easier. that way I could tell what is normal .
Thanks folks for all the help Randy