If the slides work on 110, then the motors are ok. It has to be a 12-volt problem
Does every other 12-volt item work--fridge on 12? Is the 12-volt shutoff switch in the service door set to off? If the push/pull silver knob is in, the slides will not work, but the landing jacks will. Check on that.
I have an '05--the slide power is hydraulic on mine, so I am guessing you still have the push/pull knob in the area where the front jack controls are on the outside.
Hope this helps.
And, welcome to the forum.
2016 Tiffin 40 QBH
2015 38RSSA, traded
2005 TK3 #1869, 10 yrs of memories,
2017 F450 KR--one more Ford is it
2009 F450 4x4-died; 2010 F450-retired