SKR Pro1.2 X-Endstop issue

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If the endstop is showing triggered when it isn’t activated, you have an open circuit. Check your connections, especially if you are using an extension cable. Also test the switch itself to ensure you are connected to COM and NC, and that the switch is 0 Ohms between COM and NC when not asserted.

If you are using the crimp connectors, check that you crimped on the metal, not the insulation (use an Ohmmeter). Solder connections are permanent, but more effective (IMO), depending on your solder skills

EDIT - I initially misread your post, the following isn’t your issue - but you might experience it later…

There is also a known issue with the SKR Pro v1.2 endstops . But the symptoms would be different - M119 would not show triggered when the switch is activated (even though the lights are asserted). Some users claim that it affects a small number of boards, but IMO the problem is regrettably common.

You could search the forum for “SKR endstop resistor” and find dozens of threads, but in summary there are limited options:

  • Cut the trace on the LED (destructive, will void warranty)
  • Solder a resistor (1k - 1.5k Ohm) to the underside of the board at each connector VCC 3.3V to SIG terminals (will void warranty)
  • Fabricate a “pigtail” that jumpers the resistor between VCC 3.3V and SIG terminals on the board connector end (requires 3 pin female connectors) and connects to the endstop cables on the other end (requires 2 pin male connectors). (Does not void warranty)

I used the pigtail method with a 1.2k Ohm resistor. Again, if you search the forum for “SKR pigtail” you will find dozens of posts, but this post shows the schematic and a picture of the pigtail. I suggest making the pigtail a bit longer (4"-5" ) so that you can have the cables connect under the board, rather than on the top or side.