Are you suspicious that your Auto-Leveling Probe (aka Z Probe) may be malfunctioning? Some users have seen the Z axis go upwards when they click home or when running the Auto Leveling Process (G29).
You can run a quick test by issuing the following commands in your software.
The read-back from your M119 command should be as follows:
- x_min: open
- y_min: open
- z_min: open
The term "open" indicates that the end stops or probe are not closed or "TRIGGERED". In the image below, you can see an example of each axis (X, Y, then Z) being homed. In this example, the M119 command is given after each axis is homed, reporting the axes being "TRIGGERED" one by one. If your commands look like this, the end stops, probe, and Printrboard are functional. If not, see the table below for further diagnosis.
To diagnose, power OFF your Printrbot. Disconnect the Z probe from the "Z-STOP" port on the Printrboard. Next disconnect the Y end stop from the "Y-STOP" port on the Printrboard and plug it into the now available "Z-STOP" port. Lastly, plug the Z probe into the "Y-STOP" port.
After "swapping" your probe and Y end stop. Send the M119 command again. See the table below for diagnosis on which components may need replacing.
|Y & Z swapped||open||open||TRIGGERED||BAD||FUNCTIONAL|
|Y & Z swapped||open||TRIGGERED||open||FUNCTIONAL||BAD|
|Y & Z swapped||open||TRIGGERED||TRIGGERED||BAD||BAD|