what is the power drive button for on a 1999 isuzu trooper

The power button changes the shift pattern to keep it in a lower gear longer, mainly for pulling a trailer on hills (highly recommended to use it before getting to the hill and keep out of overdrive). Winter button should start out in 3rd gear reducing torque so you have better traction taking off on snowy/icy roads.4-speed automatic features a winter mode. When it's engaged, the transmission starts out in third gear to prevent wheelspin on icy or snowy surfaces. The transmission also has a power mode that gives better acceleration by raising up-shift points. Both modes are controlled by well-placed pushbuttons in the center console."Winter drive - you must be going under 7 mph when you engage it. It keeps the SUV in 3rd gear (max ~ 40 mph) so that speed is reduced, control is better. Useful for when roads are slick with snow/ice, especially curvy, hilly roads. Power drive - gives slightly more power when accelerating. Increases the RPM's for each gear. Mileage will suffer, though.

Agree,

is there a fuse for the air compressor air condition to come on the air condition is not kicking in.

is there a fuse for the the power drive button?