PSA: don't trust those cheap USB voltage testers on Amazon

I had a client's laptop come in last week with a dead charging port. Found out after digging that she was using a $8 USB tester from Amazon to check her chargers. Those things can backfeed voltage through the data lines if the pinout is wrong. Fried the controller chip on her board. I replaced the port and chip but it cost her $180. Has anyone else seen damage from those little testers or the inline power meters?

2 comments

2 Comments

lopez.jana1mo ago

Oh man, YES. I had a similar thing happen with a little inline power meter I got for like ten bucks. Plugged it into my phone to check charging speed and next thing I know the phone won't even turn on. Took it to a repair shop and they said the meter sent voltage back through the USB data pins and blew the charging IC. Cost me $150 to fix. Learned my lesson the hard way.

jackson.matthew1mo ago

I mean, I get what you're saying about that power meter frying your phone, but maybe it's just me, I've had pretty good luck with those cheap testers. I've been using a $7 one off Amazon for like two years now on all kinds of stuff, laptops and phones, never had a problem. Idk, it feels like a lot of times the real issue is maybe the charger or the cable is already toast before you plug the tester in, and the tester is just the scapegoat. I've seen plenty of dead charging ports on laptops that had nothing to do with a tester, just bad cables or dirt in the port. Not saying your repair guy was wrong, but sometimes those shops blame the easiest thing.