With Apple's M1 CPU, the iPad Pro 2021 is a powerful tablet, but when updating or restoring the OS, certain users may run into Errors 1100 or 1101. These issues usually arise when updating, flashing, or recovering iPadOS on a PC. Restore failures, iPad screen stuck on the Apple logo, or even problems like the device flickering and not booting up are some of the symptoms. Phonefix will walk you through every stage of the troubleshooting process in this post, from simple fixes to more complex fixes, so you can find and fix the problem fast.
I. Meaning and Differences of Errors 1100 and 1101
Understanding the error types is the first step to accurate repair:
· Error 1100: This often points to a hardware-level issue with the NAND flash memory chip, such as a poorly soldered chip, storage anomalies, or a dropped drive.
· Error 1101: This typically indicates a software connection failure or data transfer interruption, potentially caused by issues with the USB port, driver mismatch, or firewall blocking.
II. Phase 1: Preliminary Software and Connection Environment Troubleshooting
1. Check the computer system and iTunes/Apple device app versions.
· On a Mac, go to System Preferences > Software Update to ensure the system and Finder support the latest iPadOS.
· On Windows, upgrade to the latest version of Windows and install the latest Apple device apps, or update to the latest version of iTunes.
2. Replace the data cable and connector.
Use an original Apple USB-C cable or an Apple MFi-certified cable; avoid cheap third-party cables.
· Use a Current Voltage Tester to check if the data cable is providing stable power.
· Loose cables or insufficient power can easily cause an 1101 error.
3. Restart the device and disable security software.
· Force restart the iPad: Press Volume Up → Volume Down → Press and hold the top button until the Apple logo appears.
· Temporarily disable antivirus software or VPN tools to prevent firewalls from blocking the flashing process.
4. Change your computer and network environment.
· Try using another computer (macOS or Windows).
· Change your Wi-Fi network to avoid bandwidth-limited or firewall-protected environments (hotspots or home broadband are recommended).
· Use a network speed test tool to check for sufficient download bandwidth.
· Restoring the iPad is not recommended on a company intranet or public Wi-Fi.
III. Stage 2: Update iPad Using Recovery Mode
Try to resolve system crashes or failed flashing without erasing data.
Steps:
1. Connect your iPad to your computer using an Apple USB-C Charge cable;
2. Quickly press the Volume Up key, then the Volume Down key, then press and hold the top button until the "Connect to Computer" screen appears;
3. Identify your iPad in Finder (Mac) or iTunes/Apple Devices app (Windows);
4. Select "Update." The system will download and attempt to reinstall iPadOS.
Notes:
· If the download takes longer than 15 minutes, the device may exit Recovery Mode and need to be re-entered;
· If there is freezing, flashing again, or the restore fails, proceed to the next stage.
IV. Stage 3: Factory Restore in Recovery Mode
Erase all system partitions in the storage area and test whether the iPad Pro NAND flash memory is still writable.
Steps:
1. Enter Recovery Mode again;
2. Select "Restore" instead of "Update" on your computer;
3. The system will automatically erase all data and download the latest iPadOS;
4. After the system is flashed, the device will reboot to the welcome screen.
Failure Signs: If you receive error 1100 during this step, or if the device crashes or reboots mid-flash, it's likely that the NAND chip is damaged or unable to write.
V. Phase 4: Motherboard Hardware Repair
Before proceeding with hardware repair, the screen and motherboard must be removed and inspected and operated using professional ipad tools.
1. Disassembly Preparation
· Ensure the iPad is completely powered off.
· Use a hot air gun to heat the edges of the screen to facilitate prying.
· Use a suction cup, plastic opening tool, and anti-static gloves to safely remove the screen and back panel.
· Use a screwdriver set to remove the metal cover and shield securing the motherboard.
2. Inspect the NAND Flash Chip
The NAND chip is the iPad's main memory. Common models include Toshiba or SK Hynix and are located in the lower-middle area of the motherboard.
Common faults include:
· Chip desoldering or poor soldering;
· Chip aging and inability to write properly;
· Broken communication line between the main controller and iPad Pro NAND flash memory.
Instructions:
Step 1: Motherboard Separation and Pre-treatment
· Use a suction cup or heat gun to carefully separate the iPad's screen, disconnect all cables, remove the shield, and remove the motherboard.
· Secure the motherboard on a preheating station and preheat to approximately 150-180°C in preparation for subsequent operations.
Step 2: Removing the NAND Chip
· Use a HD trinocular microscope to locate the NAND chip. After applying flux, use a hot air gun (300-350°C) to evenly heat the solder balls until they melt.
· Use anti-static tweezers to gently remove the chip, avoiding damage to the motherboard pads.
· Clean any residual solder from the motherboard pads, ensuring they are smooth and shiny. Clean the removed chip thoroughly for subsequent handling.
Step 3: Data Reading and Migration
· Insert the old chip into a PCIe NAND programmer to read and back up key identification information such as the serial number and ECID.
· If the chip is physically damaged, the repair is terminated. If it is readable, write the data to a new, blank chip of the same model.
Step 4: New Chip Balling and Installation
· Secure the chip and cover it with a soldering screen. Apply solder paste and heat to form even balls.
· Align the newly implanted chip with the motherboard solder pads and use a hot air device to precisely solder it to the motherboard according to the temperature curve.
3. Test the Recovery Flash Function
· After reinstalling the chip, connect the computer directly to the recovery mode without reinstalling the monitor. Observe whether the system can be successfully flashed and activated.
· If the system can be flashed and the error code disappears, the NAND has been successfully replaced and motherboard functionality has been restored.
VI. Check Other Related Circuits or Chips
If the 1100 error persists after replacing the NAND, further check the following components:
· Power Management IC (PMIC): Provides stable voltage to the NAND;
· Power inductor and filter capacitor: Filters out noise and interference;
· Controller chip communication pins: Connects bus signals between the controller and the memory chip.
Use a digital multimeter or digital oscilloscope to check each voltage node for abnormalities. If there are short circuits or excessive voltage drops, replace the corresponding components.
VII. Apple Official Support
For this type of failure, if the device is not damaged, has not been disassembled, and is still within the one-year warranty or AppleCare+ coverage period, the recommended options are:
· Visit an Apple Store or Apple Authorized Service Provider;
· Obtain an official inspection report for repair or replacement services.
VIII. Repair Recommendations
iPad Pro 2021 errors 1100 and 1101 are caused by multiple factors:
· Error 1101 can usually be resolved by updating the software, changing cables, or switching to a different network.
· Error 1100 is often a direct indication of a iPad Pro NAND flash memory hardware failure and requires resolving with methods such as desoldering and chip programming.
Avoiding frequent power interruptions and forced shutdowns is advised in daily life to extend the flash memory's lifespan. To prevent further harm to the device during the repair procedure, it is advised to flash the device using the professional iPad repair tools that China Phonefix provides. Watch this space for more excellent material!
