Troubleshoot

[MakerJim]

@draglinetrash

Endstop and plug problem is eliminated I believe it is a board/firmware problem but not sure what to do now.

There’s a chance you have an SKR pro with a known issue.

Here’s the thread where it was first identified:

Lowrider V3 Endstops Do Not Trigger

Here’s what I’ve found. Attached is the schematic for the limit switch connectors from BigTreeTech manual for the SKR Pro. [image] There’s a 4.7K pullup resistor and a 1K current limiting resistor to the LED. I measured 1.7V across the LED which is fairly typical for a red LED. Looking at the voltage divider of the 4.7k/1.0K resistor, the voltage for pin 3 (signal pin) calculates to 1.98 V which is pretty much what we have measured with the DVM. So… the question is what changed? Why does …

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Here’s a thread showing how this can be fixed by soldering on resistors:

Z axis homing - 1 side dropping

I was able to take a photograph while assembling my LR3 with the strut plates and new YZ plates. Hope this helps. [image]

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Here’s a thread showing how this can be fixed by making a wiring pigtail adapter with integrated resistor:

Problem with x not stopping when homing

Below are photos of how to make a pigtail to solve the pullup problem without soldering to your board or do anything overly complex. Items required: 1.5k resistors HiTec Servo Terminal Kit Crimp Tool Heat Shrink Tube Process in photos: [pigtail1] I make the smallest little white wire possible so it can go into the connector and also be flexible so it can fold over in your case. I then solder the resistor wire (shortened of course) to the white wire. [pigtail2] [pigtail3] [pigtail4…

[draglinetrash (William Rice)]

did a M119 showed z2_max: Triggered .
Manually triggered all endstops did a M119
15:19:48.643 : N82 M11916
15:19:48.643 : Reporting endstop status
15:19:48.643 : x_min: TRIGGERED
15:19:48.643 : y_min: TRIGGERED
15:19:48.643 : y2_min: TRIGGERED
15:19:48.643 : z_max: TRIGGERED
15:19:48.643 : z2_max: TRIGGERED
15:19:48.643 : z_probe: open
15:20:01.221 : N83 M10528
Then Jogged machine away from endstops , did M119 again showed this
15:58:03.981 : N25 M119*29
15:58:03.981 : Reporting endstop status
15:58:03.981 : x_min: open
15:58:03.981 : y_min: open
15:58:03.981 : y2_min: open
15:58:03.981 : z_max: open
15:58:03.981 : z2_max: open
15:58:03.981 : z_probe: open
Original board seems to work now . Does M119 change anything or just Diag?

Will try to run a cut file later and report back. Then if all good will install NEW SKR Board and check M119 on that one.

[MakerJim]

@draglinetrash

Does M119 change anything or just Diag?

M119 doesn’t change anything. It’s just diags.
Anytime the machine is not acting correctly, this is the detail anyone will want to see to help troubleshoot.

If something is acting up, I manually trigger and untrigger that endstop. WHILE it is kept in either state I pull M119s. You should do a few, intermittent problems are hard to diagnose.