I have a couple of Alchitry AU’s from the kickstarter and they no longer power up when connected via USB, though they do via the separate power in.
When I check the voltage on the SK34 with the USB pluuged in only, there is nothing on the anode.
Do you have the part number and pin out for the original connector please? I’d like to get these boards working again (I also have the newer sparkfun edition with the QRIIC conector and I can see that’s a different USB C connector and they both work fine).
Many thanks.
The original connector was Molex 1054500101. This is a full USB C connector and when SparkFun took over they wanted to use a cut down version that was easier to assemble (no hidden pins).
We still use these on the Ft as the full set of pins are needed.
It seems unlikely the connectors are bad. I’d check for a short and continuity first. It may just need a little flux and to be heated to fix a bad joint. If you would like, you can send them back for repair.
Thanks, I’ve done some conituity tests, all passed so far, but there’s a bunch of pins on the underside I can’t get to sadly… I may have a quick go with some flux and a fine tip…
You said it’s not getting power right? If you can, I’d check for continuity on the power lines from the USB cable to the board. This would make sure the break is at the connector and not somewhere else.
Yes, I just need to find a dead USB C cable, or one I can chop the ends off, the accessible pins seem ok (pin to solder continuity passes).
Just beeped it end to end and it beeps ok, Tomorrow I’ll look at tracing the track from the diode to the power chip.
This seems pretty weird. With the cable plugged in an powered do you not see power at the board side?
No, no power.
It makes me wonder if the CC1 & CC2 pins need rework…
I’ll do some more checks later in the week, I think I have a way to do another test 
Have you tried it with a basic USB 2.0 A to C cable? This would eliminate any CC issues.
oh, good call… YES they work with regular USB A-C cables!
Do you know which pins and which resistors on the board s(i.e. their positions) relate to the two CC pins?
I’m fairly sure that I made the mistake of using one 5.1K resistor for both CC pins on the original batch. This is likely the issue. Looking through the archives, it looks like I fixed this 5 years ago almost to the day.
The only real solution is to use a USB C<->A cable.
No problem, I have 4 AUs (two kickstarter, one sparkfun and one 100K sparkfun) so I have plenty of options, thanks for confirming.
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