Firmware issues?

  1. Can’t home X and Z, motors run to the home switch, press it and keep on going.

First, I’d run your display in Marlin mode by holding the knob down for a couple of seconds, then reboot the board and verify the right firmware is on the board. Alternately, you can send an M115 to get the firmware info. I just want you to verify that you have dual Lowrider firmware on the control board.

Second, as Ryan suggests, post a picture of your M119.

Assuming the firmware and M119 check out, then it looks like you have a control board issue. There is a design weakness in the SKR Pro that, when combined with out of spec components, results in problems detecting the limit switches. This is the topic where the issue was first identified, and there are several other topics on the issue. This issue is rare, but common enough to generate several topics on the forum.

Your choices are 1) exchange the board for a new one, 2) disconnect the LEDs associated with the limit switches by either unsoldering them or cutting their traces, or 3) add a pullup resistor for the limit switches. Most people add the resistors. It can be done destructively by soldering the resistors. This post shows how it can be done. It can also be done without modifying the SKR Pro board. Here is a post where the resistor was added to the wiring.

4 Likes