Purchase defective. Need exchange

I just bought the SKR pro 1.2 from you and it’s defective. I couldn’t find anywhere else to get help with an exchange.

The x endstop is reporting open even with nothing connected. All other endstops report correctly as triggered.

Unless I can remap the x endstop pinout to the unused endstop connection??

An exchange may still be needed, but are you sure that you bent/clipped the diag pin on the X driver? With that connected only the sensorless homing can trigger that endstop.

The thing with the LEDs drawing too much current usually makes the firmware think that the switch doesn’t get triggered, even though the LED lights up. Sounds like rhat could be, too. Does the LED next to the X motor port light up when the switch is triggered?

Does the switch work on other ports?

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I bent all the drivers before installing them.
The switch works as intended in other ports, other switches that work fail in the x_min port.
The LED light works but looks “blocked” by something. The lights on the others are bright. The LED on the X motor is dim with a pin hole of light near each solder joint but looks like something is blocking the light in the middle. I tried to take a picture but it gets washed out by the light and doesn’t show in a picture
The LED light turns on and off with the switch but the open state does not change with the light.
I can hook up a 100K resistor by itself from + to S and it shows triggered, however, if I connect the switch and the resistor together it reverts back to open.
It would be nice if I could change pinouts for x_min from PB10 to PG5.

The machine is wired correctly. This is a straight swap to the SKR board from RAMPS which was working 100%.

EDIT: I just tested the voltage at the switch and all working switches have 2.0v the x has 1.6v. Would disabling the LED be the way to go? I don’t want to damage something and not be able to exchange/ return it.

You can do this, in the pins file. It isn’t easy finding the right one. But it is in there somewhere.

There are a few reports of this. Some resistors they used for the LED circuit are too small, and the pullup isn’t pulling it up enough.

You seem like you know what you’re doing. So I would trust your judgement. Removing an led or resistor will fix it. Or you can add a pullup resistor to get it working. It really sounds to me like a manufacturing goof up to me.

@vicious1 is the final arbiter of these decisions. He would decide what is ok and what isn’t. I am not going to speak for him.

I can swap it out if you would like. Most don’t have this issue, but for some reason a couple do.

You can try adding a resistor to the pins, or removing the LED. This has fixed it for everyone that has tried it here.

Biqu has finally acknowledged the issue after many attempts by many people. New updated boards are still a ways out, they told me the back stock is ~3,000 boards.

Sorry for the hassle, let me know what you decide. (working hard on exploring options behind the scenes)

I was tempted to throw the whole machine out the window. I figured I’d try to disable LED first, THEN throw it all out the window.

After removing the LED and checking voltage at the switch I was getting 3.2v. I booted it up and the switch was working correctly.

The solution was to remove the little LED.

Now I get weird connection issues when I boot up where nothing wants to respond as far as move and home commands. Sending an M119 or any other move or position request during the “outage” seems to just hang and timeout with a blank terminal readout. All the touch screen buttons work but it says “printer not connected”. I usually have to power cycle a few times for it to start working correctly. Running a 2 hr test cut now to see if it drops out during a cut. I’m about 45mins in and so far so good. I suspect it’s one of the data cable connections from the touch screen to the main board.

Everything does take about a minute or a bit more to actually boot and handshake.

The 1.6V does sound like a pullup resistor to me.

I had trouble with one of my (non BTT) boards before, and I resolved it with the plug-in for the switch by adding a 1k resistor between the signal and +5V pins on the board. This got me a reliable trigger for the endstop every time without needing to alter the firmware or re-define the board. This required me to re-crimp the board end connector with a 3 pin end, but no soldering so no problems with the board status.

Personally, I like having the LEDs for the end stops.