Tabletop moves transversely freely . Transverse movement inoperable. Longitudinal movement functioning.

I couldn't figure out why this is. The longitudinal movement looks like it's powered by a chain and motor. But the transverse movement seems to be powered by two little plastic gears? I haven't been able to study the schematic so i'm just going off what I can see. But that doesn't seem correct as I can't imagine two little plastic gears sturdy enough to move a 600lb patient side to side. So if it's not the gears what belt or chain do I need to find and how do I access it? And why is it not operating? Did it slip off? Thanks for all your help everyone.