LR3, All components verified good, motor still not moving

LowRider CNC Troubleshooting
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Either i’ve got the worst luck with these SKR pro v1.2 boards, or something is fundamentally wrong with what i’m doing.

Having an issue on a new build for an LR3. First two of the SKR boards I used had a burned out Z1 endstop connector. Could not make the LED light when the endstop was triggered, and the voltage coming from the signal line to ground was 1v lower than the rest of the endstops.

I finally get another board in, reinstall all my wiring, and go to testing. X works, Y works, but on Z, only the Z2 motor will move.
Conducted troubleshooting to see if it’s a dead motor, motor works when the Z motor positions are swapped. Motor works.
Conducted troubleshooting to see if it was a dead stepper driver. Swapping driver positions between Z1 and Z2 had no change. If it was a dead driver, it’d have caused only Z1 to move and Z2 to be cold. As this isn’t the case, neither stepper driver is dead.

M119 command shows all endstops as open. Testing each endstop (with exception of probe) showed endstops are properly named and associated, and show as open unless actuated. All actuated endstops show as “triggered” as expected in a NC configuration.

M122 command shows all connections as “OK” with driver registers on 0x80:16:00:C0 for all drivers.

Still not getting any movement from the Z1 port on this board. Also attempted to move the Z1 motor from the usual port to the normally jumpered port, no change. It’s like there’s nothing coming out of the Z1 driver, even though the driver responds as OK.

I’m willing to accept if i’m making a wiring mistake or there’s a problem with Firmware, but I’m at a complete loss, and my wits end. Photos of board connections are possible, but terminal output is gonna be a bit more difficult.

Sidenote:
Admittedly, previously had a wiring issue with my endstops as being in the wrong locations (Not sure why we’re putting Y2 driver on E0 motor connection, but not on the E0 endstop connection, but whatever.) Fixed to align with proper wiring locations listed on the SKR Pro electronics page. Triple checked with additional second party people rechecking my work.

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Endstops don’t restrict movement unless you are homing. So they aren’t affecting the motor or driver.

Plug the Z motor into the Y port or something and see if it is something in the motor wiring (motors don’t really fail) or the driver/socket.

Are any of the flags checked in M122? ola, olb, s2g? I don’t want to do the work to parse the bytes you sent. Make sure you check after you have engaged the motors (by trying to jog each axis).

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It has to do with some legacy stuff with Marlin.

While BTT labels those as X, Y, Z, E0, E1, E2, Marlin considers them as XMin, YMin, ZMin, XMax, YMax, ZMax.

For other reasons, putting an X stop on the Y axis causes Marlin to lose its marbles a little. But… we still manage Z2 on the XMax in the LR versions (because ZMin has to be the touchplate because.)

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I received your request, i’m trying to do some further diagnosis to come back with.
So far:
When I ran the previous M122, I missed the part where my “Enabled” flags were all false. So the previous M122 is probably useless. Now, when I attempt to move all axes, the other four motors register with 0x80:16:00:00 but my Z1 motor still shows 0x08:16:00:C0.

I moved the Z1 motor to the X motor port on the board, and the Z1 motor turns fine with jogging.
I was trying to see what happens when I move the X motor to the Z1 motor port, but every time I tell it to jog in that lineup, it causes the other Z2 motor to uh… rotate at high speed and cause the motor to “bottom out”?

EDIT: Also meant to add in, there’s OLA and OLB flags set inside the M122, but… I can’t tell which ones it’s for? This TFT35 screen is really showing some limitations already.

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I appreciate the information on it. It doesn’t really change anything on my end, I was just frustrated that some of my issues were because I mis-associated which endstops went to each endstop port, because I was matching them as “Y2 is E0, so Y2 endstop must be E0 endstop.” Which was obviously wrong.

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Ola is open loop on A coil. Olb is open loop on b coil. So there is probably a wiring issue. M122 is tough on the screen. It is easier with an attached computer.

Check the solder joints and the dupont connector on the Z1 port. You can also try swapping the drivers and see if the problem follows the drivers or the port. It seems like the issue is between the driver and the wire for the motor, since you have ola/olb and the wires and motor work in X port.

Don’t ever hot swap the motor wires or drivers. I should have warned you before the last post.

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I appreciate anyone that looked at this post. I hate to say it, but I changed out the board with another one of my SKR Pro boards that I thought the endstop wasn’t working on. Turns out that the LED on it may not be lighting up, but it’ll still register as triggering the endstop. Couple that with me wiring the endstops into the wrong ports (See Dan’s post about legacy stuff in Marlin), made me make a bad assumption about the board being broken.

This one I was trying to use is definitely broken, probably similar to the post in (Various wiring issues with the X- and Y-axis (SKR Pro V1.2, TMC2209, Dual Endstops)! - #19 by diff-arch) and there being a bad solder joint somewhere.

I’m not tech enough to fix it, i’ll just use that board as a 4 motor beast somewhere else.

Thanks for reading!

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Thanks for all your help. Ola and olb being open loops on the stepper makes sense for why it wasn’t moving.

All the solder joints looked good, no cold joints that I was able to see. The affected motor port was doing some weird stuff when I was probing for continuity on the board motor port, so it’s probably a failed component or a broken trace or something else related to the Z ports. Frustrating, but not the end of the world.

And yeah, hot swapping connections was how I burned out board #1. I learned the painful way.

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