‘Dead iPhone’ trick lets you make Apple Pay payments and even unlock car with zero phone battery

JUST because your iPhone's battery is all out of juice doesn't mean you're carrying a useless brick around.

It turns out that you can make some kinds of payments and even unlock your car using a dead iPhone.

Even though your iPhone doesn't have enough power to fully run, it can still have enough juice to carry out some low-level tasks.

Here are two situations where it can still work.

HOW TO USE IPHONE POWER RESERVE

The first situation where it can work is Apple Pay – but note that you can't make any old payment without battery.

It specifically only works with transit, and makes use of Apple's Express Mode feature.

Express Mode lets you set a default card for your iPhone to use with public transport.

And it means you don't have to unlock the device to make the payment.

So if you're tapping into the London Underground or New York City subway, you can just tap your locked iPhone and your default Express Mode card will be charged.

Express Mode is turned on by default, but you can change the card by going into your Apple Pay settings.

And it turns out that this feature can still work with low power.

However, it's strictly limited to transit payments – and won't let you buy a coffee from a shop, for instance.

The same is also true for any keys or passes that you've got saved to your Apple Wallet.

So if you followed our guide for setting up your car key on iPhone, you can use that too.

Apple explains: "You might be able to use your Express Mode cards, passes, and keys on your iPhone, even when your device needs to be charged.

"Power reserve works for up to five hours with some cards, passes, and keys that have Express Mode turned on."

To see if it's going to work for you, just press the side button while your iPhone needs to be charged.

It should reveal which cards, passes, and keys can be used on power reserve.

That's important, as some keys might not support the feature.

However, Apple warns: "Doing this often might significantly reduce the power reserve."

It's also important to note that this feature does not work if you've manually switched your iPhone off.

Your iPhone has to specifically run out of charge for you to be able to use it.