Damn thing has suddenly stopped working. Are these fixable "in the field"? Or should we continue to climb in and out like HGV drivers? I can try unbolting everything and taking a look inside. Does anyone know whether that will just result in parts flying in all directions when I open it up, or is there some chance of me being able to diagnose the problem at least, even if I can't fix it. I can give a detailed description of the problem, but I just wanted an indication of whether these are best left to the professionals.