The Original Prusa MK4/MK3.9 is equipped with a loadcell, to detect that the nozzle is close enough to the steel sheet for printing, and to avoid damage that would be caused by the nozzle digging into the steel sheet.
The printer firmware expects a measurement sample from the loadcell to occur within a specified time. In case this does not happen, the printer will show the message "There was a timeout while waiting for measurement sample, please repeat the action."
Error name: Loadcell Timeout
Error code: #13528 (MK4) #21528 (MK3.9)
First, make sure you have the latest firmware.
Access the LoveBoard, locate the loadcell connector and cable, and check for any loose cable, disconnected cable, or visible damage. The loadcell connector is indicated with the orange arrow in the picture below.
Navigate to LCD Menu - Calibration - Diagnostics - Test Loadcell to restart the loadcell test.
During the test, you will be asked to tap the nozzle at a specific time, and a progress bar on top of the screen will be filled. If the progress bar is not filled or the printer shows any errors, please contact our customer support.