Please lower the printer to the bottom, then turn off the printer and disconnect the power supply to ensure safe operation.
(1)First remove the filament tracker cable, then use the S2.0 Allen key to unscrew the two screws fixing the filament tracker and remove it, and finally remove the teflon tube.
(2)Use the S2.0 Allen key to unscrew all screws on the back cover, and then remove the back cover of the printer.
Use the S2.0 Allen key to loosen the five screws on the fixing plate of the cooling fan, and then remove the fixing plate.
After removing it, please check whether the Z-axis motor connection on the mainboard is loose, and then reinsert the motor cable.
If the printer still reports this error after removing and inserting the motor cable, then the Z-axis motor cable may be damaged. Remove the Z-axis motor line from the motherboard, and then adjust the multimeter to the buzzer setting to measure the connection of the Z-axis motor line. If the meter does not sound, you need to be replace a new Z-axis motor cable.
If there is no problem with the motor cable, then please set the multimeter to the buzzer gear and measure the on-off condition of the Z-axis motor. If the meter does not sound, then the Z-axis motor is damaged, please follow the instructions below to replace the Z-axis motor.
Kobra S1-Z axis motor replacement guide
If there is no problem with the Z-axis motor, then the strain gauge needs to be checked. Please remove the print head case and check whether the strain gauge cable on the adapter plate is loose and deformed. If the strain gauge is damaged, please replace it with a new one.