Hi DR Chambers,
I do not know Aerbus so this may or may not apply. Somewhere there is a pump that moves the fluid to move the slide. This pump may be 12 VDC powered. If this is true, consider obtaining a portable starting battery (any auto parts store) and connect 12 VDC to the pump connections. If the slide opens and retracts normally, the problem is upstream from the slide mechanism. There may be a slide controller that is at fault.
A caution. If you do this be very careful. You are bypassing all the safety features of the slide. Once connected, if the slide moves the wrong way, reverse the leads. When the slide is at full travel one must remove the power manually. The slide will continue to operate until power is removed.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours