I think your driver jumpers need to be removed and one added to the far left.
Please verify. Wrote you move around as I am supper newb too and don’t want you to “let the smoke out” or hurt something.
https://docs.v1engineering.com/electronics/skrpro/
The uart stuff and other options I haven’t fully understood yet.
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Hi Kev, hi Travis,
thanks for these suggestions and thoughts.
I swapped the drivers so many times, here are the results:
Numbers in brackets represent yesterdays setup
Yesterdays setup:
20:12:17.393 : Testing X connection… Error: All LOW (1)
20:12:17.409 : Testing X2 connection… OK (2)
20:12:17.424 : Testing Y connection… Error: All LOW (3)
20:12:17.447 : Testing Y2 connection… Error: All LOW (4)
20:12:17.462 : Testing Z connection… Error: All LOW (5)
X2 and X1 swapped:
20:37:40.692 : Testing X connection… Error: All LOW (2)
20:37:40.708 : Testing X2 connection… Error: All LOW (1)
20:37:40.723 : Testing Y connection… Error: All LOW (3)
20:37:40.755 : Testing Y2 connection… Error: All LOW (4)
20:37:40.777 : Testing Z connection… Error: All LOW (5)
Swapped again (setup as yesterday)
20:40:59.417 : Testing X connection… OK (1)
20:40:59.417 : Testing X2 connection… OK (2)
20:40:59.449 : Testing Y connection… Error: All LOW (3)
20:40:59.464 : Testing Y2 connection… Error: All LOW (4)
20:40:59.487 : Testing Z connection… Error: All LOW (5)
Swapping X1 and Y1, as well as X2 and Y2:
21:11:02.876 : Testing X connection… OK (3)
21:11:02.907 : Testing X2 connection… Error: All LOW (4)
21:11:02.907 : Testing Y connection… OK (1)
21:11:02.929 : Testing Y2 connection… Error: All LOW (2)
21:11:02.945 : Testing Z connection… Error: All LOW (5)
Swapping X1 and Z:
21:17:22.426 : Testing X connection… Error: All LOW (5)
21:17:22.448 : Testing X2 connection… Error: All LOW (4)
21:17:22.448 : Testing Y connection… OK (1)
21:17:22.464 : Testing Y2 connection… OK (2)
21:17:22.480 : Testing Z connection… Error: All LOW (3)
Back to yesterdays setup:
21:22:49.889 : Testing X connection… OK (1)
21:22:49.905 : Testing X2 connection… Error: All LOW (2)
21:22:49.905 : Testing Y connection… OK (3)
21:22:49.921 : Testing Y2 connection… OK (4)
21:22:49.936 : Testing Z connection… Error: All LOW (5)
Unplug and re-plug of Y2 and Z:
21:25:19.564 : Testing X connection… OK (1)
21:25:19.564 : Testing X2 connection… OK (2)
21:25:19.580 : Testing Y connection… OK (3)
21:25:19.596 : Testing Y2 connection… OK (4)
21:25:19.611 : Testing Z connection… Error: All LOW (5)
Unplug and re-plug of Z:
21:26:33.106 : Testing X connection… OK (1)
21:26:33.122 : Testing X2 connection… Error: All LOW (2)
21:26:33.122 : Testing Y connection… OK (3)
21:26:33.138 : Testing Y2 connection… OK (4)
21:26:33.153 : Testing Z connection… Error: All LOW (5)
Wait for a bit, switch on again:
22:18:28.830 : Testing X connection… OK (1)
22:18:28.846 : Testing X2 connection… OK (2)
22:18:28.846 : Testing Y connection… OK (3)
22:18:28.861 : Testing Y2 connection… OK (4)
22:18:28.877 : Testing Z connection… Error: All LOW (5)
Switch off, switch on:
22:20:28.654 : Testing X connection… OK (1)
22:20:28.654 : Testing X2 connection… OK (2)
22:20:28.669 : Testing Y connection… OK (3)
22:20:28.685 : Testing Y2 connection… OK (4)
22:20:28.701 : Testing Z connection… Error: All LOW (5)
Swapping Y1 and Z:
22:22:13.807 : Testing X connection… OK (1)
22:22:13.823 : Testing X2 connection… Error: All LOW (2)
22:22:13.839 : Testing Y connection… OK (5)
22:22:13.839 : Testing Y2 connection… OK (4)
22:22:13.870 : Testing Z connection… Error: All LOW (1)
Switching back:
22:24:18.051 : Testing X connection… Error: All LOW (1)
22:24:18.067 : Testing X2 connection… Error: All LOW (2)
22:24:18.082 : Testing Y connection… OK (3)
22:24:18.082 : Testing Y2 connection… OK (4)
22:24:18.098 : Testing Z connection… OK (5)
Same driver setup, both grey serial cables disconnected form board and tft:
22:27:28.667 : Testing X connection… Error: All LOW (1)
22:27:28.698 : Testing X2 connection… Error: All LOW (2)
22:27:28.698 : Testing Y connection… OK (3)
22:27:28.713 : Testing Y2 connection… OK (4)
22:27:28.720 : Testing Z connection… OK (5)
Summarized: All driver responded in at least one port - which is good. But why do they work sometimes and somestimes not and how can I get all of them to work? I pushed 'em in correctly, each time. I am super confused.
Heres a proper picture of the board, sorry for the misleading image before Travis:
And one, showing the connection between board and tft:
Any thoughts?
Cheers and good night,
Karl
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And after swapping a bit more, this happend:
22:43:59.678 : Testing X connection… OK
22:43:59.694 : Testing X2 connection… OK
22:43:59.694 : Testing Y connection… OK
22:43:59.709 : Testing Y2 connection… OK
22:43:59.709 : Testing Z connection… OK
I carefully plugged in stepper motor and tft cables. NO TMC ERROR. The CNC moves for the first time <3 In the end, did a lot of pulling out and pushing in of the drivers do the job? Did anyone experience that before?
No Z movement so far - I gues the “repaired” pin might be the reason for that.
And the scrambled tft in Marlin mode still existent and I read from many others on reddit who share this problem with the BTT TFT 35 V3. I might buy another tft to skip this… Any recommendations?
Cheers, Karl
If those are melted as it looks like, take a close up picture of the opposite side of the board. This board may have crappy solder workmanship on the flip side, and if so it may explain intermittent operation.
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By the sounds of it, maybe the pushing/pulling could have fixed whatever the problem was? We are pretty sure it’s an intermittent connection or intermittent short somewhere along the driver circuit. Could even be shorting on the aluminum box.
Wow guys, good eyes!
This picture confirms the melting:
And here’s the flip side. Couldn’t spot any bad soldering work though.
Maybe the board was shortcutted to the box and got fried a tiny bit.
It was elevated from the box by unconventional, a bit broader (compared to what is screwed to it now) spacers im the beginning. Especially the upper left corner looks like the first soldering is very close to the screw hole. Maybe the board got short cutted there.
The question remains whether the board is “fixed” now or will show repeated failures in the future. I will reconnect everything in the next days and observe it’s behaviour. If I decide to get a new board, I will install it with plastic washers between the board and the correct slim spacers.
Many thanks for your support so far!
Cheers,
Karl
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Hi Aaron,
I didn’t see that thread, many thanks! Will try that, especially because the connection seemed very weak to me before.
But this is only for the black TFT cable, correct? I am wondering why that should interfere with the marlin mode, which uses the grey ribbon cables if I am not mistaken.
Cheers,
Karl
Yep, that’s my understanding from Jeff’s post too. So probably won’t fix.
That back side view looks to me like the solder work on those driver headers is pretty suspect.
If you have it out again, any chance of a close-up on at least one driver set?
I suspect that you have intermittent solder joints from bad workmanship and this will be a problem at times until those get re-flowed.
I agree with MakerJim. The reason the solder looks suspect to me… the top most slot appears to have what may be a cold solder joint (grey looking with dark ring around pin)… yet the others that melted appear they were reflowed (which would happen with all the heat). Maybe it reflowed itself enough to work again?
Hi MakerJim,
Wow. I really know nothing about boards and soldering 
thanks for staying with me and your suggestion
I am not 100% sure whether you wanted a close up of the back side of one of the driver slots, but that would be here in different angles, as good as my camera can do.
Does that help?
Cheers,
Karl
Hi Kev,
Well, it would be awesome if it somehow fixed itself. When it did, it should be permanent, correct? Meaning, if I pull and re-insert the drivers, they should work all the time. That would be easy to find out and I highly doubt it 
About the scrambled TFT, I read others posts on Reddit, describing the same problem also with other boards. With some describing, that they have the exact same configuration on several machines and only some exhibit these problems. Which would indicate a not to rare hardware problem of the BTT TFT35 V3 E3. Is there anything that I can only do with the TFT in marlin mode? Otherwise I’d ignore this problem until I stumble over a solution and use the touch mode and PC for everything.
Cheers,
Karl
Yeah relying on “self reflowed” connections is a bit sketchy. If they do work reliably… ie replug all of them several times and no fails… then it may be reasonable to look the other way. Personally, I’d resolder new connectors on… but I do crazy things all the time. Worst case though, is a driver disconnecting in the middle of an expensive peice of stock that has had several hours of work put into it already. Replacement hardware isn’t cheap, but the alternatives that come with sketchy hardware can sometimes be worse.
I personally only use Marlin mode on my printer… don’t use a tft on my cnc, since it has an rpi with a gcode sender on it. AFAIK, you don’t strictly need touch mode to use a stock mpcnc. I have read some threads where folks are working on getting touch mode to be more cnc friendly. Having a working touch mode may be a good thing as that matures.
Replying again after seeing something in the latest photo post… the board I think should be replaced. There are several areas on the underside of the PCB that appear to have heat damaged solder resists (areas where the “paint” looks crinkled up… may flake right off with a light touch). If this is the case, the PCB has been compromised too much for continued use IMHO.
Next board, definitely do take care of insuring those standoffs aren’t shorting traces. I bought a kit of nylon standoffs from Amazon that I use for this sort of thing if I don’t feel like printing a mount. The kit came with assorted length nylon standoffs, nylon nuts, and nylon screws. So you never have to have metal touching a PCB.
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I’m in agreement with Kev- I wouldn’t trust that board after whatever happened to cook it.
If I were really in a bind, I might scrape off any charring and try to white wire any stressed traces- but if I were going to do something like that, it’d mainly be to use it as a software development mule and not as a production board.
Probably the most important thing for you to do now is to figure out if that overcurrent and meltdown happened because something in your setup is allowing the through hole leads to short on something (a case or a metal plate, etc.) If so, you should fix that ASAP.
Sad to say, but those drivers are suspect too- if something in that system got hot enough to do that, they are likely to have been stressed.
Is there any chance you got a “refurbished” board. I’ve seen crap like that on quite a few things I got from Amazon- due I suspect to their easy return policy and less than scrupulous sellers.
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Hey guys,
Thanks alot for your expertise!
I’ll get a new board and will try the current drivers first. If they act suspecious, I’ll order new ones.
If I understood you correctly, the problem is a combination of a bad quality board and (most likely) a short in my setup which finally cooked the board. Would you say the board quality is a warranty case? Well, I got it from the v1 shop so Jeff and Ryan can follow the case thereselves 
Let’s see, maybe the new board will also improve the TFT behaviour…
Fingers crossed, I’ll keep you updated!
Cheers,
Karl
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