Auto bed leveling with BL Touch sensor crashing to bed I'm new to 3d printing and I recently bought a Geeetech Prusa i3 Pro B along with a BL Touch (3D touch) sensor to do auto bed leveling.

I printed the sensor holder, mounted it and the sensor to the extruder carriage and uploaded a configured Marlin firmware to the printer. It worked great for about 6 times and now, it crashes on the bed on the two points on the right of the bed.

I tried manually leveling the bed thinking that the nozzle was touching the bed plate before the sensor's needle could, but that's not the case. Even with the bed manually leveled, when using G29 (Auto Bed Leveling code), the Z-axis carriage crashes into the bed.

What can I do/check?
As it turns out, my Z-axis carriage mount to the X-axis was bent, causing the nozzle to touch the bed before the proble could get a chance to detect anything. Manually bending it back to the correct angle solved the problem.