This error refers to a problem with the Z limit switch, which is located at the back bottom side of the Ultimaker. The limit switch is used for homing the build plate and ensures the build plate won’t move down any further when it is at the bottom of the Ultimaker.
When this error shows up it however means that the Z limit switch is not activated. This can either be caused by a problem with the movement of the build plate on the Z axis, or a problem with the limit switch itself.
The following steps are advised to resolve an issue with the Z axis or limit switch:
- First of all, check if the build plate is going down completely while homing. If it doesn’t, check if there is nothing lying under the build plate that could prevent the build plate from moving down completely
- Manually move the build plate down and check if you hear a “click” when it is at the bottom. If not, continue with the next steps
- Check the hole on the back side of the bottom panel (where the Z limit switch is located) and make sure there are no small pieces of filament in there that could prevent the lever from switching properly
When the switch is being pressed (correctly), but not working after taking the above described steps, there is possibly an electrical cause for the problem. For further assistance you can contact one of our local service providers.