The iPhone screen is black but notifications and calls can still be heard, indicating a "Black Screen of Death" issue. Potential causes include a low battery, app crashes, or hardware issues like burned out resistors. Troubleshooting steps include charging the phone, restarting it by pressing volume and side buttons, updating crashing apps, and for hardware issues, replacing burned resistors using a hot air gun at specific temperatures and air flows.

1. A problem that sometimes appears is the iPhone Black Screen of Death. The phone
screen is black, but the iPhone 11 can still hear notification and calls. Sometimes,
the screen may be off, in any case, the screen remains off.
Before you start to lose your mind and stress out, try some troubleshooting first
and there are some things to solve this problem at home. This issue is common and
it can happen due to multiple reasons. A few of these reasons include:
1. Check Your iPhone 11 Battery
May be your battery is drained, so you need to check your iPhone 11 Battery. The
case is possible, and it often happens. Plug your iPhone into the charger and press
the home button. If the Apple logo appears, you are safe and just avoided a rather
uncomfortable experience.
2. Restart your iPhone

2. If you can hear notifications from text messages or phone calls, the screen will be
dark and there will be no response. This problem usually indicates that the iPhone
is frozen or crashed. The simplest solution is to restart the force.
(1). Quickly press then release the Volume Up key.
(2). Quickly press then release the Volume Down key.
(3). Press and hold the iPhone Side Button for about 10 seconds then release when
you see the Apple logo.
3. Update the Crashing App
When you use an unsafe app loadssomething, likestreaming apps, your phone may
stuck on black screen of death.
Exit the app, enter the App Store and tap on the Updates section. If there are any
available updates, specifically for the app that is crashing, install them and restart
your iPhone.

3. 4. Hardware Issues
When your iPhone was dropped or got wet, it will get stuck on black. It time to
check your hardware. Here is an hardware repair case that the burned out resistors
lead to black screen.
 Step 1. Using diode mode of the multi meter to measure diode values of pin 26,
24, 22, 20, 18, and 16 on J8000 and observe whether there is an open circuits
in the circuits of the two pins after remove the screen and disconnect the
battery.
 Step 2. Remove the shielding cover with QUICK 2008, and protect the
connectors with high-temperature tape.
 Step 3. Replace the two burned out resistors R5651 and R5661. Apply some
Solder Paste Flux and disassemble the resistor. Apply some medium
temperature solder paste and continue heating. Solder the two inductors with
a heat gun.

4.  Step 4. Remove the High-temperature Tape, measure whether the diode values
of pin 24 and 18 return to normal with multi-meter.
 Step 5. The phone can be turned on and its display is working properly. So far,
iPhone 11 black screen issue has been repaired successfully.
Tips:
1) Setting a Hot Air Gun to disassemble the resistor at 360°C and an air flow of 40.
2) Remove the resistors with Hot Air Gun at 360 °C and airflow 40.
3) Keep heat gun at 380℃, and the airflow 60 for soldering the inductors.
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