Daylight Saving Time Caused Some Apple Watch S4 Devices to Crash, Reboot Endlessly

A bug related to daylight saving time (DST) caused some Apple Watch Series 4 devices to crash repeatedly in Australia over the weekend.

According to reports from impacted users on Reddit, the bug appears to specifically affect the Infograph Modular watch face. Specifically, the issue seems to be tied to that watch face’s Activity complication, which displays an hour-by-hour timeline graphic for Move, Stand and Exercise data.

Users who had the Infograph Modular watch face with the Activity complication reported that their Apple Watch Series 4 models got stuck in an endless crash-and-reboot cycle until they finally ran out of battery.

How Did This Happen?

Apparently, when the DST time change chopped an hour off the day in Australia on Saturday, the Infograph Modular watch face didn’t handle it well. In other words, the watch face was unable to deal with a 23-hour day.

Luckily, users reported that functionality returned to normal once the date rolled over to the next day with a full 24 hours.

How Did Users Resolve This Issue?

Other impacted Apple Watch Series 4 owners indicated that they were able to fix the problem by opening the Watch app on an iPhone and switching to a different watch face — as long as it’s not the Infograph or a related face.

It’s worth noting that even selecting the Infograph Modular face with the Activity complication on the iOS Watch app will cause the app to crash indefinitely. So try to stay as far away from that face as possible.

On the other hand, if you do find your Apple Watch Series 4 stuck in an endless reboot loop, we recommend leaving it alone until it dies. Putting it back on the charger won’t fix it, it’ll just prolong the cycle — and could cause long-term battery damage.

While the issue fixed itself organically after a day, we expect Apple to release a software update to squash the bug. That’s especially true since similar DST time changes are just a few weeks off in other countries and regions of the world.

For example, in the U.S. and Canada, DST ends on Sunday, Nov. 4. In many parts of Europe, DST ends on the last Sunday of October.