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Weird cable with USB A connector with 5 pins (discuss.tchncs.de)

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

7 comments fedilink hide all child comments

Hello, I recently bought a USB A to C cable and it is pretty weird. It is a USB A to USB C cable, seemingly USB 2.0 but the A connector has 5 pins, the 4 pins of USB 2 and what looks like pin 7 of USB 3.0 so in the middle of the back row, the other pins of USB 3.0 are not there and the plasting moulding only allows for that one pin (moreover the USB type C end looks like it only has the few middle pins so it's probably 2.0). The weirdness continues because when connected to a USB power supply the led on the USB C connector lights up but it can only charge simple devices like flashlights or things that generally just accept 5V, anything with fast charging capabilities gets no output. I am probably going to test it with breakout boards and eventually even disassembly it and maybe replace the connectors but in the meantime does anyone have any explanation?

P.S. I will make a follow up post (or an update here) when I open it up, with photos of course.

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[–] [email protected] 8 points 1 year ago (1 children)

Pics would be helpful

[–] [email protected] 1 points 1 year ago

I am pretty busy this week, I am posting when I have breaks and I don't have it with me. When I'll have the time I will make a post with photos and measurements and I will probably also open it up.

[–] [email protected] 3 points 1 year ago (1 children)

In my experience, if they don't include the conductor in the connector, there will generally not be a wire for it in the cable. So replacing the USB-C connector is probably not going to add any functionality.

I have a stack of USB-A to USB mini/micro cables that are a bit like this. Two conductors, only do charging. So if I replace the connector, there's no wire to connect the D+ / D- lines to. It's quite possible the manufacturer of your cable had some similar or otherwise reduced feature set in mind, and wanted to save 5 cents of copper.

I also have some cursed cables that have normal ports, but only two wires inside the cable (power/ground), or are otherwise out-of-spec in ways that make the data lines mostly fail. These have wasted quite a bit of my time over the years.

[–] [email protected] 1 points 1 year ago

I only need a USB 2.0 cable mostly for charging, I have better cables, I chose this one for the liquid silicone outer layer. Of course if the wires inside are less than four or too thin I won't waste USB connectors (that I already have, I would not order them for this) and I will recycle it.

[–] [email protected] 2 points 1 year ago (1 children)

Sounds like you bought a crappy cable. Why not just buy a good one instead of disassembling and replacing stuff?

My guess is that it needs the fifth pin to trick some devices to think that it’s a 3.0 cable instead of a 2.0 with a c connector.

[–] [email protected] 2 points 1 year ago (1 children)

Type C 2.0 exists and is widespread and that is what I wanted, the issue is that it doesn't work as a 2.0 cable either. I like the liquid silicone exterior and I have a few connectors ready so if I like what's inside I may upgrade it. Otherwise I will recycle it and I already have better cables.

[–] [email protected] 1 points 1 year ago

Hey fair enough. If you are really concerned about what it if you could always reach out to the manufacturer