How To Fix an iPhone 15 Pro That Randomly Restarts: Difference between revisions

How To Fix an iPhone 15 Pro That Randomly Restarts
Device	iPhone 15 Pro, iPhone 15 Pro Max
Affects part(s)	Main Logic Board
Needs equipment	Screwdrivers, known good parts, spudger
Difficulty	◉◌◌◌ Easy
Type	Part replacement

Latest revision as of 00:40, 13 December 2023

Problem description

There are many reasons that could cause an iPhone 15 Pro and iPhone 15 Pro Max to randomly restart every few minutes. For the iPhone 15 Pro series, there are some sensors within the parts of the phone that are required to be plugged in & detected. Otherwise, the phone restarts on its own.

The most common for iPhone 15 Pro series are:

Charging Port Flex - This is the flex towards the bottom of the phone. It is easily damaged with a drop & the back glass is breaks. Or when someone has repaired the back glass.
Back Glass/Wireless Charging Flex - This is the flex that wraps around the logic board & controls the power button.

iPhone 15 Pro Max - Wireless flex diagram. If it's unplugged, it will restart giving panic log error 0x400000
Bad Battery - If the battery is defective or goes bad, it can cause restarting problems.

Symptoms

After a back glass repair, the iPhone will restart on its own every few minutes
After a hard drop, the iPhone will restart every 3 minutes.
After a screen repair, the iPhone will bootloop every 3 minutes
After replacing the charging port flex, the device will auto restart on its own randomly.
The iPhone will reboot randomly when using it.
The iPhone will seem to freeze and restart every 2-5 minutes.

Solution

Diagnostic Steps

Before you start blindly replacing parts, it's important to try to confirm what is causing the restarting issue by reviewing the Panic Log file. This is a file that is generated by the Operating System, to document the fault causing the restart.

To find the panic log on the device, go to Settings-> Privacy-> Analytics & Improvements-> Analytics Data-> Scroll down to the files starting with "panic-full..." & click on the most recent dated file.

Then you'll want to scan through the text for keywords that may point you to the cause.

For this model, look for where it says "SMC PANIC - ASSERTION FAILED" ... "Sensor Array" .. "0x...."

If you see:

0x300000 - It's the Charging Port Flex

iPhone 15 Pro Max Panic log example. It will restart if the charging port flex is unplugged, causing 0x300000 panic log error
- iPhone 15 Pro Max will restart if the charging port flex is unplugged, causing 0x300000 panic log error
  Make sure this flex is plugged in
- Check that no flex is torn, liquid damaged, defective
- Test with OEM or Premium. Aftermarket Flexes have a high defect rate
- Diode mode the FPC connectors for any fault
0x400000 - It's the Wireless Charging Flex on the Back Glass
- Make sure this flex is plugged in
- Check that no flex is torn, liquid damaged, defective
- Test with OEM or Premium. Aftermarket Flexes have a high defect rate
- Diode mode the FPC connectors for any fault
  
  Panic Log Example of 0x400000, which is due to the wireless charging flex being unplugged
0x700000 - It's 2 problems: Charging Port Flex and Wireless Charging Flex
- Make sure both flex cables are plugged in
- Check that no flex is torn, liquid damaged, defective
- Test with OEM or Premium. Aftermarket Flexes have a high defect rate
- Diode mode the FPC connectors for any fault
0xa1 - It's a battery data issue.
- Sometimes you'll see the battery percentage fluctuate or you'll randomly get a "non-genuine" message.
- Check the battery connector pins. Sometimes they can bend out & battery won't make good contact.
- Diode mode the battery connector pins & compare them to known good board
- Test with a known good battery
- Replace the battery connector
- iPhone 15 Pro Max - Device will restart every 3 minutes if the battery is bad, giving error 0xa1

Alternatively, you can use a tool like the iDevice Panic Log Analyzer, which will download the panic logs from the device & display them on the PC & give you suggestions to possible solutions. It makes it easier to browse the panic log file.

Also check out www.PanicFull.com which allows you to upload the panic log file & have it analyzed for free.

Both of these tools just give suggestions, which aren't always correct, as there is no official solution list from Apple. So many solutions are just suggestions based on hearsay, rumors or just guesses.

For situations where you don't see the above examples, you'll have to read through the top portion of the panic log & try to decipher what could be the root cause. Look for keywords you may recognize.

Repair Steps

When trying to solve for these issues, make sure to replace the appropriate flex with an OEM or Premium flex.

It is also a good idea to keep a known good power button flex & charging port flex in your bench, for testing only. There are reports of even NEW flexes being bad. So you have to keep known good flexes on hand at all times, so you don't waste your time troubleshooting with possibly bad flexes.

In scenarios where you have the appropriate flexes plugged in, but it still restarts, then you either have:

Bad or damaged flex
Low quality aftermarket flex
Other flex cables that are Liquid Damaged

Please note: You MUST have the required flex cables, (Charging port flex, Wireless Charging Flex, etc) plugged in. Otherwise, it WILL restart. You cannot troubleshoot this step by unplugging the bad flex.

@@ Line 12: / Line 12: @@
 The most common for iPhone 15 Pro series are:
-*'''Proximity Flex''' - This is the flex that is attached to the screen. It can easily be liquid damaged or torn during a screen replacement.
 *'''Charging Port Flex''' - This is the flex towards the bottom of the phone. It is easily damaged with a drop & the back glass is breaks. Or when someone has repaired the back glass.
-*'''Power Button Flex''' - This is the flex that wraps around the logic board & controls the power button.
+*'''Back Glass/Wireless Charging Flex''' - This is the flex that wraps around the logic board & controls the power button.[[File:IPhone 15 Pro Max - Wireless flex diagram.png|thumb|iPhone 15 Pro Max - Wireless flex diagram. If it's unplugged, it will restart giving panic log error 0x400000]]
-*'''2 Layer Sandwich''' - Requires the bottom layer of the 2 layer motherboard.
+*'''Bad Battery -''' If the battery is defective or goes bad, it can cause restarting problems.
 ==Symptoms==
@@ Line 30: / Line 29: @@
 ===Diagnostic Steps===
-Before you start blindly replacing parts, it's important to try to confirm what is causing the restarting issue by reviewing the Panic Log file. This is a file that is generated by the Operating System, to document the fault causing the restart.[[File:Panic Log List.png|thumb|An example of panic log files you'll find in the iPhone when it has been randomly restarting.]]To find the panic log on the device, go to Settings-> Privacy-> Analytics & Improvements-> Analytics Data-> Scroll down to the files starting with "panic-full..." & click on the most recent dated file.
+Before you start blindly replacing parts, it's important to try to confirm what is causing the restarting issue by reviewing the Panic Log file. This is a file that is generated by the Operating System, to document the fault causing the restart.
+To find the panic log on the device, go to Settings-> Privacy-> Analytics & Improvements-> Analytics Data-> Scroll down to the files starting with "panic-full..." & click on the most recent dated file.
 Then you'll want to scan through the text for keywords that may point you to the cause.
@@ Line 37: / Line 40: @@
 If you see:
-*'''0x80000''' - it's the <u>Proximity Flex Cable</u>
+*'''0x300000''' - It's the <u>Charging Port Flex</u>[[File:Charging Port Flex Panic Log.png|alt=iPhone 15 Pro Max Panic log example. It will restart if the charging port flex is unplugged, causing 0x300000 panic log error|thumb|iPhone 15 Pro Max Panic log example. It will restart if the charging port flex is unplugged, causing 0x300000 panic log error]]
-**Make sure this flex is plugged in
+**[[File:Charging Port flex diagram.png|alt=iPhone 15 Pro Max will restart if the charging port flex is unplugged, causing 0x300000 panic log error|thumb|iPhone 15 Pro Max will restart if the charging port flex is unplugged, causing 0x300000 panic log error]]Make sure this flex is plugged in
-**Check that no flex is torn, liquid damaged, defective
-**Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-**Diode mode the FPC connectors for any faults
-*'''0x40000''' - It's the <u>Charging Port Flex</u>
-**Make sure this flex is plugged in
 **Check that no flex is torn, liquid damaged, defective
 **Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-** Diode mode the FPC connectors for any faults
+** Diode mode the FPC connectors for any fault
-*'''0x10000''' - It's the <u>Power Button Flex</u>
+*'''0x400000''' - It's the <u>Wireless Charging Flex</u> on the Back Glass
 **Make sure this flex is plugged in
 **Check that no flex is torn, liquid damaged, defective
 **Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-**Diode mode the FPC connectors for any faults
+** Diode mode the FPC connectors for any fault[[File:Panic Log Example of 0x400000.png|alt=Panic Log Example of 0x400000, which is due to the wireless charging flex being unplugged|thumb|Panic Log Example of 0x400000, which is due to the wireless charging flex being unplugged]]
-*'''0xc0000''' - It's the <u>Prox Flex</u> and <u>Charging Port Flex</u>
+*'''0x700000''' - It's 2 problems: <u>Charging Port Flex</u> and <u>Wireless Charging Flex</u>
-**Make sure both flex cables are plugged in
-**Check that no flex is torn, liquid damaged, defective
-**Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-**Diode mode the FPC connectors for any faults
-*'''0x180000''' - It's the <u>Prox Flex</u> and <u>Power Button Flex</u>
 **Make sure both flex cables are plugged in
 **Check that no flex is torn, liquid damaged, defective
 **Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-**Diode mode the FPC connectors for any faults
+**Diode mode the FPC connectors for any fault
-*'''0x140000''' - It's the <u>Power Button</u> and <u>Charging Port Flex</u>
+*'''0xa1''' - It's a battery data issue.
-** Make sure both flex cables are plugged in
-**Check that no flex is torn, liquid damaged, defective
-**Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-**Diode mode the FPC connectors for any faults
-*'''0x1c0000''' - It's the <u>Charging Port</u> and <u>Power Button Flex</u> and <u>Prox Flex</u>
-**Make sure all 3 flex cables are plugged in
-**Check that no flex is torn, liquid damaged, defective
-**Test with OEM or Premium. Aftermarket Flexes have a high defect rate
-**Diode mode the FPC connectors for any faults
-*'''0x20000''' - It's a sandwich board issue.
-**This means the sandwich board has separated. It could require a sandwich reball or a bottom board swap.
-*'''0x41''' - It's a battery data issue.
 **Sometimes you'll see the battery percentage fluctuate or you'll randomly get a "non-genuine" message.
 **Check the battery connector pins. Sometimes they can bend out & battery won't make good contact.
@@ Line 81: / Line 61: @@
 **Test with a known good battery
 **Replace the battery connector
-[[File:0x41 Panic Log.png|thumb|iPhone 14 Pro Max - This panic log says 0x41, which is related to battery data is missing.]]
+**[[File:IPhone 15 Pro Max - Battery issue.png|alt=iPhone 15 Pro Max - Device will restart every 3 minutes if the battery is bad, giving error 0xa1|thumb|iPhone 15 Pro Max - Device will restart every 3 minutes if the battery is bad, giving error 0xa1]]
-[[File:0xc0000-paniclog.png|thumb|Example of what you'll see in a panic-full file, where when there's a bad prox flex and bad charging port flex causing the 3 min restart.]]
 Alternatively, you can use a tool like the [https://github.com/waynebonc/iDeviceLogAnalyzer-public iDevice Panic Log Analyzer], which will download the panic logs from the device & display them on the PC & give you suggestions to possible solutions. It makes it easier to browse the panic log file.
-[[File:0x180000.png|thumb|Example of what you'll see in a panic-full file, where when there's a bad prox flex and bad power button flex causing the 3 min restart.]]
 Also check out [https://Www.PanicFull.com www.PanicFull.com] which allows you to upload the panic log file & have it analyzed for free.
@@ Line 103: / Line 82: @@
 *Low quality aftermarket flex
 *Other flex cables that are Liquid Damaged
-Please note: You MUST have the required flex cables, (Prox flex, Charging port flex, Power Button Flex, Sandwich reballed) plugged in. Otherwise, it WILL restart. You cannot troubleshoot this step by unplugging the bad flex.
+Please note: You MUST have the required flex cables, (Charging port flex, Wireless Charging Flex, etc) plugged in. Otherwise, it WILL restart. You cannot troubleshoot this step by unplugging the bad flex.