P.I.N.D.A. Probe testing

Updated 2 months ago ​by Martin Lexa

Our PINDA probe is a vital component for the calibration of the Original Prusa i3 MK2/S and MK3. If you want to make sure that it works correctly, follow this guide.

Testing the PINDA probe 

We will go over 3 rounds of tests. So if you suspect there's an issue with the P.I.N.D.A., whether it works as expected or not, you can do the following: 

Testing that the P.I.N.D.A. probe works

In the first test, we will check if the P.I.N.D.A. probe works at all. For this test, you will need a thin object that contains metal (e.g., a spatula or scissors) 

  1. Go to the LCD Menu - Calibration - Show pinda state
  2. In the meantime, place the spatula underneath the P.I.N.D.A. probe.
  3. Z value should change from 0 to 1. If the value changes, move to the 2nd test. 
    1. Firmware 3.3.0 red light should turn off on the top of the probe.
  4. If the value does not change, make sure that your PINDA probe is connected correctly. Please refer to our MK3 EINSY miniRAMBo electronics wiring or MK2/MK2S miniRAMBo articles.
Before firmware 3.3.0, the item in the menu was called "Show endstops".
Firmware version 3.3.0 does not have the "Show end stops" nor Show pinda state menu at all.  (You were still able to use the red light located at the top of the P.I.N.D.A. as a reference)

Testing the PINDA probe cable

If you passed the previous test, it means that the PINDA probe registers metal objects and therefore is functional. Now, we must check whether the PINDA probe cable is not damaged.

  1. Push the knob next to the LCD and hold it for 3 seconds. This will enable you to move the Z-axis up and down by turning the knob. Turn the knob clockwise to raise the extruder at least 10 cm above the heatbed.
  2. Go to the LCD Menu - Calibration - Show end stops.
    1. Firmware 3.3.0 does not have the Show end stops menu at this moment. Therefore, you can use the red light located at the top of the  P.I.N.D.A. as a reference if the probe works or not.
  3. In the meantime, with your hand, move the extruder from one side to the other
  4. Z value should remain at 0. If the value changes, then the PINDA probe cable is faulty. Most likely there is an overtightened zip-tie, which causes the PINDA probe cable to fail when it reaches a specific position. Double-check all the zip-ties and make sure they are not too tight. 
    1. Firmware 3.3.0 red light should remain off.
    Testing the P.I.N.D.A. probe readings in PronterFace  

    In the last test, we will check the real values of the P.I.N.D.A. probe readings. 

    For the sake of consistent measurements, please perform the tests under identical conditions. 
    1. Connect the printer according to the USB and Pronterface guide.
    2. Ensure the nozzle is clean and the print surface is clear of any obstructions.
    3. Issue a "G80" command this will start the mesh bed leveling process.
    4. Once the process is complete, send a "G81" command, this will report out the interpolated Z values for a 7 x 7 array that composes the mesh bed.
    5. Repeat the process at least 3 times.
    6. Compare data points for each reported 7 x 7 array.

    You want to make sure there are no significant deviations (>0.2) between measurements. Keep in mind that the numbers in the matrix have their pre-defined positions, so always compare the numbers in the same positions.

    If you were not able to resolve the problem, then contact our support at info@prusa3d.com (include some photos of the P.I.N.D.A. probe cable), and our team will help you out. 

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