Google engineer Benson Leung has been using his spare time to test USB Type-C cables, and has recently found what could be the worst of them all. As rapporteret af Ars Technica, the 3M USB A-to-C cable from Surjtech fried Leung’s Chromebook Pixel, along with two USB power delivery analyzers, when used normally.
As soon as Leung plugged in the USB cable to his Twinkie USB PD analyzer, it fried the Vbus line, causing permanent damage that couldn’t be fixed via any firmware resets or reflashes. When plugged into his Chromebook Pixel, it fried both USB Type-C ports, causing neither to function as a charge or host device.
But it gets even worse. An embedded controller in the Chromebook Pixel was also fried by this Type-C cable, preventing the device from booting as Chrome OS’ Verified Boot couldn’t verify the controller. The Pixel currently only boots into recovery mode.
Upon closer inspection, Leung discovered that the Surjtech cable was “completely miswired”. Whoever designed the cable had wired the Vbus pin on one end to the GND pin on the other. On top of that, a 10 kΩ pull-down resistor was used instead of the required 56 kΩ pull-up resistor, and SuperSpeed wires were completely missing, preventing this cable from functioning at its advertised USB 3.1 speeds.
Beung stated i sin anmeldelse that he would be contacting Surjtech directly to report this “fundamentally dangerous” cable, which is designed incorrectly in practically every way possible. This is just another warning to make sure you’re buying reputable USB Type-C cables before you use them with any sort of expensive technology.