Risk of Damage

[KenH]

One of the reasons I bought the tester was that I was working on a homebuilt machine, and the front USB ports weren't working. Since I didn't have any kind of tester, I plugged in one of my old flash drives. Something inside the drive glowed BRIGHTLY for a second, and there was a smell of burning electronics. The drive is now dead. I tried another old flash drive, and that one worked.

So now I'm in a bind. I checked the wiring and it all looks correct. At least the cable from the front port is plugged into the right place. I don't know whether or not the flash drive just decided at that moment to go bad, or there's something wrong with the motherboard. The port doesn't work, at least at 2.0 speed, which might just mean the cable is inadequate, but I still can't tell just what's wrong.

I'd like to use the loopback tester to diagnose the port, but I'm reluctant to plug it in to this machine and possibly have it toast itself. How vulnerable is the tester to over-voltage, shorts, and other problems? Can anyone think of any reason for this problem, and how I might test it?

Thanks.

[David (PassMark)]

With 4 wires there are about 50 different wrong wring combinations (including shorts and breaks), but only one right combination.

So buy a cheap multimeter and check the +5V is on the right pin. If this is OK it is unlikely you are going to blow anything up that wasn't going to blow up by itself.

Or even cheaper, connect a LED and diode in series to check the voltage and ground pins.

But if your USB flash drive works, the basic wiring is almost definitely correct.

We don't promise our plugs will be OK in all bad wiring situations.

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David