I have a 1999 Winnebago Minnie and I am having trouble either the electric slide out. I know the system works, because I can jump across the solenoids and it will extend it retract, but I can not get it to work off the switch. I change the relay. At the switch, I get power in the BBB wire coming from the circuit breaker, but there is no power in the EB wire. Where does that wire come from and what could be the problem?