iPhones Pause MagSafe Charging During Continuity Camera
Well, this is embarrassing. In “Going All in on MagSafe for the iPhone in the Office, Bedroom, and Car” (6 May 2024), I wrote about how I’d found a Continuity Camera mount that incorporated an Apple MagSafe Charger so a long meeting wouldn’t impact my iPhone’s battery. Although I had installed the mount and tested it to make sure it worked, I hadn’t used the iPhone for Continuity Camera with the MagSafe Charger for a long meeting at that point.
Two days later, I was distressed to discover after a long Zoom meeting that my iPhone’s battery was quite a bit lower than when I started. Subsequently, a 90-minute meeting caused the battery level to drop from 100% to 75%. The Settings > Battery screen clearly indicated that charging had been on hold due to camera streaming during that time. What was going on? Surely the iPhone would charge when connected to a charger?
When I researched the topic more closely, I found that Apple implies that an iPhone should be able to charge during Continuity Camera, saying:
If you need to charge your iPhone while Continuity Camera is turned on, use a USB cable for best results.
Apparently, “best results” means “if you want it to work at all.” However, another Apple page about Continuity Camera is more blunt:
Continuity Camera works wired or wirelessly. To keep your iPhone charged while in use, plug it into your Mac or a USB charger. Your Mac will notify you if iPhone battery level gets low.
Apple seems allergic to saying that an iPhone won’t charge with MagSafe during Continuity Camera. However, it may not charge over USB either. Several users in a Reddit conversation reported that their iPhones lost charge during Continuity Camera sessions, even while plugged in.
I suspect that Continuity Camera taxes the processor sufficiently that the iPhone heats up. (It’s always warm when I take it off the mount after a meeting.) Since MagSafe charging also causes the iPhone to get warm—warmer than USB-based charging—Apple’s battery optimization system may be putting charging on hold to protect the battery from thermal overload. Which is good, if unexpected in the moment.
The practical upshot is that if you use Continuity Camera, you should expect your iPhone’s battery to drop, potentially significantly. If that’s a problem for you, you can try plugging the iPhone in via USB, but even that may not help. Using a mount with a MagSafe Charger, as I do, at least ensures that the iPhone will start charging again after your meeting.
I could be wrong, but I recall being on low battery during a continuity call and using my USB cable to charge it during that time. I will have to check this more closely in the future. Thanks for the heads up.
I sometimes have a similar issue when using my iPhone to navigate in my car, while connected to power with a cable, sometimes it will not charge. In the Battery settings there will then be a message stating charging was paused due to high temperature.
Wireless charging generates more heat than charging by wire, so, combined with using the camera which also generates heat, I would guess the amount of heat generated becomes too high to continue charging?
I have not tried MagSafe charging for my iPhone 14 Pro, which I use as continuity camera during Zoom calls. I use a USB-A to Lightning cable plugged into a charging block and the iPhone. The charge is put on hold during the duration of the call, but the battery level at the start of the call is the same at the end, so the cable is providing the needed power.
Yes, if I’m charging my phone in the car, running a GPS map route, and listening to a podcast, it’ll sometimes pause for overheating.
This is not unusual when navigating in a car. Between the high heat from a car’s dashboard and the heat generated by a display at full brightness, it can easily trigger the “overheated, no charging” message. It may even overheat enough to force a shutdown.
For this reason, I usually use a vent-mount for mounting my phone in the car. This way the car’s AC blows across the phone, keeping it cool even on very hot days with bright sun.
I’ve occasionally also seen the “overheated, no charging” message when not driving - while playing games at home. I suspect the screen brightness (when it’s not a dimly-lit room), coupled with the high CPU usage of many games is enough to overheat it. Especially because my phone is in a silicone case, which will act as an insulator.