First, do know where the pump is located?
Next what is the voltage at the pump motor leads when you energize the slide out?
Is there power to the pump motor?
Can you hear the pump trying to run?
Amateur Radio Operator (KE5DFR)|Full-Time! - 2012 6.7L Ford Crew Cab Dually -2013 HitchHiker Champagne 38RLRSB - Travel with one Miniature Schnauzer, one Standard Schnauzer and one small Timneh African Gray Parrot