Step cover wonít retract. Yikes!
Our Phaeton is much older and our step cover is air operated.
If your's is air operated, I'd drain the air system by repeatedly pumping the brake pedal until the gauge shows zero. Then I would manually push the cover open if possible.
If you've already taken the big step and you're outside, can you look under the cover to see the actuator? Once again if it's air operated can you loosen an air line and push it open. Can you trace an airline to get to the solenoid? Does it have power? If not, maybe a blown 12V fuse.
I'm sure somebody with a rig like your will have more help. Good luck.
Denny, Connie & Shadow (former barn cat made good)
2006 Tiffin Phaeton, Cat C7, Freightliner Chassis