Put the accessory in its documented discovery mode, move it close to the iPhone, and disconnect it from any phone or computer that may have claimed it already.
A Bluetooth accessory must be powered, charged, nearby, and in its manufacturer’s discovery mode before an iPhone can pair with it. If the name appears but connection fails, first make sure the accessory is not actively connected to an old phone, tablet, computer, or another driver’s profile in a car.
When the accessory never appears
Open Settings > Bluetooth rather than relying only on Control Center. Follow the accessory manual to start pairing mode; simply turning on headphones or a keyboard may not make it discoverable. Watch for the specified flashing light or on-screen pairing message.
Charge both devices, keep them within a few feet, and temporarily turn off Bluetooth on nearby devices that have used the accessory. If another iPhone can find it but yours cannot find any accessories, restart the iPhone and check for an iOS update.
Do not enter a guessed PIN repeatedly. Use the code printed in the manual or shown by the accessory. For a car, remove an unused phone from the vehicle’s own paired-device list if that list is full.
When it used to connect
Turn the accessory off and back on, then restart the iPhone. If it still fails, tap the information button beside its name in Settings > Bluetooth, choose Forget This Device, and pair it again.
Forgetting can remove device-specific preferences. Before doing that with hearing devices, medical accessories, digital keys, or workplace equipment, check the manufacturer’s recovery instructions. Resetting all network settings is broader and is not a sensible first step because it also removes saved Wi-Fi and other network configuration.
When only the companion app cannot see it
If iOS shows the accessory as connected but its app does not, open Settings > Privacy & Security > Bluetooth and confirm that the companion app is allowed to use Bluetooth. Update the app, close it once, and reopen it.
A managed work or school iPhone can restrict Bluetooth changes. Do not remove management profiles to work around that control; contact the administrator.
Decide which company should help
Test the accessory with one other supported phone if possible. If it fails everywhere, record its model, light pattern, and reset attempt for the accessory maker. If your iPhone cannot discover any known-good accessory or the Bluetooth switch is unavailable, contact Apple Support for device diagnostics. Never send an account password or verification code with a support request.
Frequently asked questions
Why does the accessory keep reconnecting to another phone?
Many devices remember and prefer the last connection. Disconnect or forget it on the other phone, or use the maker’s documented multipoint-switching procedure.
Should I erase the iPhone?
No. Apple’s first-line checks are pairing mode, range, charge, restart, app permission, and forgetting only the affected accessory. Erasing the phone is not a routine Bluetooth fix.
Primary sources
Interfaces and policies change. We recheck the steps above against these sources and show the verification date at the top of the guide.