MacBook Pro 14 A2442 won’t turn on — USB-C power chip replacement

This MacBook Pro 14 A2442 wouldn’t turn on.

In MacBook Pros with M1 Pro and M1 Max chips it’s a well-known scenario. The 5 V regulator that powers the USB-C ports fails and lets 12 V from the main power rail through onto the 5 V line. That destroys the ACE2 controller, which manages power and communication through the port. The damage affects one side of the computer, yet the whole MacBook stops booting.

Here it was the right side: the 5 V regulator (UG800) and the ACE2 controller (UG400). I replaced both chips. The computer boots normally and all USB-C ports work 🔧

Worth knowing: a USB-C port supplies 5 V the whole time something is plugged in — in sleep mode too. It’s better not to leave drives or adapters connected overnight. If something has to stay plugged in, it’s safer to shut the computer down than to put it to sleep.

More about MacBook logic board repair.