# Y-axis on KP3S Kingroon only moves in one direction

I recently got a KP3S Kingroon 3D printer and have been trying to set it up.

After a couple of test prints, the Y-axis seems to only move in one direction. At first, I thought it was a motor issue, but when I go into the manual move directions for the Y-axis it seems that both inputs lead to the motor spinning in the same direction.

We have ruled out endstops as a possible issue. I think it might be a hardware issue but lack the skills to confirm the exact issue.

Send:17:40:57.724: @moveRel Y10.00
Send:17:40:57.724: N31 G1 Y10.00 F6000
Send:17:40:57.728: @updatePrinterState
Send:17:41:00.824: @moveRel Y-10.00
Send:17:41:00.824: N35 G1 Y0.00 F6000
Send:17:41:00.828: @updatePrinterState
Send:17:41:07.445: @moveRel Y10.00
Send:17:41:07.445: N43 G1 Y10.00 F6000
Send:17:41:07.449: @updatePrinterState
Send:17:41:09.482: @moveRel Y-10.00
Send:17:41:09.482: N46 G1 Y0.00 F6000
Send:17:41:09.486: @updatePrinterState


Even though it states that it is increasing and decreasing by 10 it only decreases by 10.

I have updated the firmware to Marlin. I tested switching X and Y inputs and believe the breakdown occurs at the Y input signal.

attached is a picture of the mother board.

I am unsure of how to best fix this?

The answer might just be replace the mother board.

If I understood everything correctly there are 5 things to check to break down the problem:

• the motor,
• the cable,
• the stepper connection,
• the software input, and
• the firmware.

Using Repetier I disproved that the software was broken. By switching the X stepper and Y stepper cables, the motor and connection cable were proven to work. By flashing new firmware it was shown that it was without question that the firmware was the issue.

The backup extractor (E1) is not operational on this board. So it is either the stepper of the mother board.

• @agarza, If i understood everything correctly there are 5 things to break: the motor, the cable, the stepper connection, the software input, and the firmware. Using repetier i disproved it was on a software that was broken. By switching the x stepper and y stepper cords the motor and connection cable was proven to work. and by flashing the firmware it was shown that it was without question firmware. the backup extractor (E1) is non-operational on this board. So it is either the stepper of the mother board. Any other ideas are welcome. Jan 9 at 18:27
• @doombringer175 Great comment, but that would be even better to fit the first line into the answer. I've taken the liberty to include this into the answer. Feel free to change it! Note that you could have changed the X stepper driver with the Y stepper driver, they are Polulu breakout boards, so you can even work out if the board or the driver is the issue! Do you mean that the E1 is not working because there is no driver, or did you also put a driver in?
– 0scar
Jan 10 at 12:38

The question body has changed to rule out broken endstops. As a generic answer for steppers only going into a single direction, if an axis of a 3D printer only moves in one direction it usually implies that the end stop of that axis is triggered. If triggered, the firmware doesn’t allow the stepper to move to the direction of the end stop.

Check the end stop lever and cables. Optionally connect a USB cable and send the G-code M119 over a terminal.

If the endstops are functioning correctly (reporting “open” or “triggered” corresponding to the state of the endstop), a Google search on the World Wide Web shows that people that had these exact problems had issues with the controller board, replacing the board helped their issue. If this is a recent purchase it is advised to contact the seller for support rather than fiddling with the board or the firmware.

In case the board has a spare unused stepper driver (not very unlikely if you have this controller board), the firmware could be altered to use the spare for Y movement. E.g. E1 could be used for Y.

• I appreciate the help, and these exerciese did help me learn more about the system. I think the system is reading both y inputs as the same command, are there codes you know of to move the y axis? it might help me figure out if its a hardware (what i am currently assuming) and a software (doubtful but really want to rule out). and if it is hardware what would be your next step? Dec 27, 2021 at 22:29
• @doombringer175 Swap the X and Y stepper connectors to see if X now only moves in one direction. Do it at your own risk, I’m not liable for damages. Also, see the bottom part of the answer, you could try to use the spare stepper driver slot. Best if you use a new driver though, but you could try with the current one. Do note if you use a new driver, you need to make sure it is the same and set the correct Vref.
– 0scar
Dec 28, 2021 at 12:35
• My skill set is more on the software side so i'd wager its not an impossible fix, but i don't think its going to be quick. I'll do some research. again i think both the motor and the cable are fine (given that it worked fine when plugged into the x drive) so i'll give it a shot. something to the effect of this right: 3dprinting.stackexchange.com/questions/3925/… Jan 7 at 14:18
• @doombringer175 There are a few ways to tackle this, 1) the previously mentioned switch of the X and Y cables only one of the connectors each cable, 2) swap the cables completely, 3) with the cables working and swapped you could pry out the X/Y stepper drivers and swap them. This should give you information whether it is cables, steppers, or the board/processor. 4) change the firmware and proceed with using the spare slot with a new driver.
– 0scar
Jan 7 at 15:25
• Comments are not meant to last forever or extended discussions or help, you are very welcome in our public 3D Printing chat room! There are more people to help you there!
– 0scar
Jan 7 at 15:28