Q1. Can I downgrade from newer to older firmware (Android 9 → 8.1)?

No. Only official QFIL RAW for your region can restore a previous system, but major downgrades often risk brick or IMEI loss.

Q2. Which firmware is safe for a phone stuck in bootloop?

Always use RAW/QFIL for your exact variant and region. Never mix JP and WW—and check device label for X01BD/ZB631KL cross compatibility.

Q3. Can I cross-flash Japan (JP) to WorldWide (WW) firmware?

Never; crossflashing different SKU/region firmware is the top cause of permanent bricking on this device.

Q4. Is there an official Asus flash tool or just QFIL?

QFIL/QPST is most reliable for RAW packages. Some "flashall" batch/fastboot tools exist, but are riskier for deep unbrick. Always download tools listed with official firmware.

Q5. After RAW flash, my IMEI is missing or "Unknown Baseband"

This means your security/NV or modem partition is wiped. Only a service center or advanced NV backup restore can fix (not covered by QFIL flash alone).

Zenfone Max Pro M2 (ZB631KL/X01BD) All Official RAW, QFIL, OTA Firmware

The Asus Zenfone Max Pro M2 (ZB631KL/X01BD, including ZB630KL overlap) is built on the Qualcomm Snapdragon 660 with a 6.26-inch display, 5000mAh battery, and stock-like Android system. This widely-flashed device features both RAW/QFIL unbrick ROMs (for EDL/9008 mode recovery or bootloop), official OTA ZIPs (for standard updates), and region-dependent packs for WW (Global) and JP (Japan) models. Correctly matching firmware and flashing method is crucial due to persistent bootloops, hard bricks after cross-regional updates, and eMMC “dead” scenarios reported in forums.

CRUCIAL WARNING: Always match your SKU/Region (WW, JP, etc) and model (ZB631KL/X01BD) before flashing. Mixing JP with WW or RAW/QFIL not intended for your region may hard-brick your phone—especially on eMMC “dead” units or if downgrading Android version. Only use RAW/QFIL packs for total brick, dead boot, or EDL 9008 mode recovery. OTA .zip files should only be installed through stock recovery matching exactly your current region and software version. Always backup data and confirm model before proceeding.

Pre-Flashing Checklist (Zenfone Max Pro M2)

Read Before You Start

Model & Region Double-Check: In Settings > About and the original box/label (WW, JP, RU, etc); X01BD and ZB631KL must match firmware exactly.
Backup Data: All flashing methods wipe apps, user data, and can wipe IMEI if QFIL/RAW used incorrectly.
Charge Battery: Above 50% and connect to a reliable PC USB port.
Qualcomm USB Drivers & Tools: Required for QFIL/RAW flash. See tutorial
Official Asus Flasher: Only use official QFIL/fastboot tools for these models — avoid “universal” flashers unless expressly stated for Zenfone.

Firmware Types & When to Use Them

RAW/QFIL Factory ROMs: For deep unbrick, bootloop, EDL (9008 mode), or “no led/no boot” after failed flash. Requires QFIL or Qualcomm QPST tool. Erases all data; risky if SKU mismatch.
OTA ZIP Updates: For typical system updates or upgrades; applied from stock recovery. Sensitive to region (WW/JP/RU) and version—do not “crossflash.”
Fastboot/Flasher Packs: Windows tools for partial repair, but reliability is much lower than QFIL/RAW when device is hard bricked.

Asus Zenfone Max Pro M2 — Complete Firmware / ROM Table

Filename	Type	Region	Android/Build	Flash Tool	Size	Link
Zenfone-Max-Pro-(M2)-ZB631KL_UL-ASUS_X01BD-WW-16.2017.2011.105-user.zip	RAW/QFIL	WW/Global	Android 9, 16.2017.2011.105	QFIL/QPST (EDL)	1.6GB	Download
Zenfone-Max-Pro-(M2)-ZB631KL_UL-ASUS_X01BD-JP-16.2017.2011.105-user.zip	RAW/QFIL	JP/Japan only	Android 9, 16.2017.2011.105	QFIL/QPST (EDL)	1.6GB	Download
WW_ZB630KL(ZB631KL)_16.2017.1908.072.rar	RAW/QFIL	WW/Global (ZB630KL & ZB631KL, some cross-flash risk—verify!)	Android 9, 16.2017.1908.072	QFIL/QPST	1.5GB	Download
WW__ZB630KL(ZB631KL)_16.2017.1908.072_20191217[bootloopdc].rar	RAW/QFIL (bootloop-fix)	WW/Global	Android 9, 16.2017.1908.072 [fixes bootloop]	QFIL/QPST	1.5GB	Download
WW__ZB631KL_15.2016.1812.179_20181227_Phone-user.raw-131916168053590584.zip	RAW/QFIL (EDL unbrick)	WW/Global	Android 8.1, 15.2016.1812.179	QFIL/QPST	558MB	Download
Asus_ZenFone_Max_Pro_M2_ZB631KL_UL-ASUS_X01BD-WW-16.2017.2010.101_OTA.zip	OTA ZIP	WW/Global	Android 9, 16.2017.2010.101	Stock Recovery (update)	1.6GB	Download
Asus_Zenfone_Max_Pro_M2_X01BD_ZB630KL_15.2016.1810.155_20181116_RAW.zip	RAW/QFIL	WW/Global/X01BD/ZB630KL	Android 8.1, 15.2016.1810.155	QFIL/QPST	1.87GB	Download
Asus_Zenfone_Max_Pro_M2_ZB630KL_15.2016.1810.155_20181116_QFIL.zip	RAW/QFIL (QFIL naming)	WW/Global/ZB630KL	Android 8.1, 15.2016.1810.155	QFIL/QPST	1.88GB	Download
Asus_Zenfone_Max_Pro_M2_ZQL1820_Factory_201812071630_ChangeFlash_QPST.zip	RAW/QFIL (Factory/EDL)	WW/Global (some SE Asia cross-use—see variant label)	Android 8.1, Factory build 20181207	QFIL/QPST	1.33GB	Download

Quick Flashing Guide

RAW/QFIL (EDL, Deep Bootloop/Unbrick, or “9008” Mode):
1. Install Qualcomm QFIL or QPST tool and Qualcomm drivers.
2. Boot device to EDL mode (test points or special fastboot command if not fully dead).
3. Load the correct RAW/QFIL firmware (e.g. Zenfone-Max-Pro-(M2)-ZB631KL_UL-ASUS_X01BD-WW-16.2017.2011.105-user.zip) in QFIL.
4. Follow all steps per complete QFIL tutorial. Start flash, wait for finish/reboot, then set up device.
5. If IMEI/Baseband lost – only restore via backup/NV or professional tool!
OTA ZIP (System Update, Recovery):
1. Copy .zip file to phone’s SD root or internal storage.
2. Boot to stock recovery (Power + VolDown) and select Apply update from SD card.
3. Choose matching update ZIP (e.g. Asus_ZenFone_Max_Pro_M2_ZB631KL_UL-ASUS_X01BD-WW-16.2017.2010.101_OTA.zip). Confirm and flash.
4. Once finished, reboot system.

Full EDL/QFIL instructions: See step-by-step guide

Common Problems and Real-World Solutions (Zenfone Max Pro M2)

Bootloop/Dead Phone After OTA or Crossflash: Often caused by mismatched WW/JP or bad update. Try EDL/QFIL with official RAW for your SKU only.
Stuck on Logo, No Recovery: Deep flash with RAW/QFIL. If not detected, require test point method (shorting contacts near eMMC) to force 9008 mode.
Lost IMEI/Baseband: Flashing RAW sometimes wipes modem/NV. Only professional repair or NV backup can restore.
Display glitches & touch issues: Usually after forced downgrade or unofficial ROM. Restore with RAW/QFIL for your hardware; factory reset after.
Screen Flicker (especially after updates): Users report improved stability after re-flashing official OTA ZIP and then performing factory reset.
Update error: “Firmware not for your device”: Means region/SKU mismatch, do NOT force update. Flash with matching WW/JP firmware only.

Frequently Asked Questions (FAQs)

Q1. Can I downgrade from newer to older firmware (Android 9 → 8.1)?: No. Only official QFIL RAW for your region can restore a previous system, but major downgrades often risk brick or IMEI loss.
Q2. Which firmware is safe for a phone stuck in bootloop?: Always use RAW/QFIL for your exact variant and region. Never mix JP and WW—and check device label for X01BD/ZB631KL cross compatibility.
Q3. Can I cross-flash Japan (JP) to WorldWide (WW) firmware?: Never; crossflashing different SKU/region firmware is the top cause of permanent bricking on this device.
Q4. Is there an official Asus flash tool or just QFIL?: QFIL/QPST is most reliable for RAW packages. Some “flashall” batch/fastboot tools exist, but are riskier for deep unbrick. Always download tools listed with official firmware.
Q5. After RAW flash, my IMEI is missing or “Unknown Baseband”: This means your security/NV or modem partition is wiped. Only a service center or advanced NV backup restore can fix (not covered by QFIL flash alone).