Test the accessory with something else
Try pairing the headphones, speaker or car with a different phone or a computer. If they will not connect to anything, the accessory needs charging, resetting or replacing — no iPhone setting will help.
Then try the iPhone with a different Bluetooth device. If it pairs with everything except one accessory, the fix is on that pairing; if it pairs with nothing, the fix is on the phone.
Check the obvious, properly
Bluetooth switched off in Control Centre only disconnects accessories until the next day; open Settings → Bluetooth and make sure the switch is on there. Charge the accessory fully — many headphones refuse to pair, or pair and drop at once, when the battery is low rather than empty.
Keep the two within a metre or so while pairing, and away from a microwave or a crowded USB 3 hub, both of which interfere with the 2.4 GHz band Bluetooth uses.
Forget the device and pair it again
Settings → Bluetooth, tap the ⓘ next to the accessory, then Forget This Device. Put the accessory back into pairing mode — usually by holding its power or pairing button until a light flashes — and pair it as if it were new.
For AirPods, put both in the case, open the lid, and hold the button on the back of the case until the light flashes white. That resets them; then hold them next to the unlocked iPhone and follow the card that appears. If they connect but drop out or misbehave, check they are on the latest AirPods firmware.
Restart both
Turn the accessory off and on, and restart the iPhone. The Bluetooth chip's firmware is reset with the phone, which clears a surprising number of connections that look broken but are only stuck. A force restart is the stronger version.
Cars and CarPlay
Cars keep their own list of paired phones, often with a limit of five or so. Delete the iPhone from the car's list as well as the car from the iPhone's, then pair again from scratch. Some cars only accept a new phone while stationary with the engine running.
If calls work but music does not, or the reverse, check Settings → Bluetooth → ⓘ next to the car, where the device type and audio routing can be set.
Reset network settings
Settings → General → Transfer or Reset iPhone → Reset → Reset Network Settings clears every Bluetooth pairing along with Wi-Fi networks and VPN settings, and rebuilds them from scratch. It is the right step when the iPhone fails with every accessory. See our network reset guide for what you will need to set up again.
On a beta, Bluetooth faults are common and often fixed in the next build — our beta guide covers that case.
When it is hardware
If the Bluetooth switch will not stay on, or the phone cannot see any device while others nearby can, after a network reset and an iOS update, the wireless hardware is likely at fault. Phones that have been dropped or wet are the usual candidates, and a repair is the only fix.
Frequently Asked Questions
Why won't my AirPods connect to my iPhone?
Put both AirPods in the case, open the lid, and hold the button on the back until the light flashes white. That resets them; hold them next to the unlocked iPhone and follow the setup card.
Why does my iPhone keep disconnecting from Bluetooth?
Usually a low accessory battery, distance, or interference. Charge the accessory, forget it in Settings → Bluetooth, and pair it again.
Why is my iPhone not finding Bluetooth devices?
Make sure the accessory is in pairing mode — usually a flashing light — and within a metre. If the iPhone finds nothing at all, restart it and reset network settings.
Will resetting network settings remove my Bluetooth devices?
Yes. Every pairing is removed, along with saved Wi-Fi networks, and you pair each accessory again afterwards. Nothing else on the phone is affected.