If an Original Prusa XL detects a crash, after it the printer will attempt to find a reference point, through a procedure called Precise homing. If the right and left sides are not aligned, the Precise Homing will fail, and this error will be shown.
Error name: Precise Refinement Failed
Error code: #17102
After correctly adjusting the belts, the two plastic parts on the sides of the rail should reach the front of the axis together.