FYI, The battery gauge inside a RV will NEVER tell you if you have a good battery, especially if you are plugged into 120 Shore Power. You can have NO battery or a completely DEAD battery and the inside monitor battery gauge will show full battery when on 120 shore power. It just reads the 12 volt dc voltage IN the RV, which will read out what the 120 to 12 volt POWER CONVERTER is putting out. Soooo, Since you stated both slide operate off on one button, that means you have a Hydraulic slide system. Which takes a GOOD fully charged Battery to operate correctly. From your description, your battery is either bad or NOT in the loop/circuit of the RV and your Hydraulic pump was attempting to run off the output of the Power Converter, which it is not designed to do. You need to check your 12 volt battery water level and have it tested and verify that it IS being charged when plugged in. Doug