Here’s the simplest method I know of for flashing a TM-AC1900 to a RT-AC68U or RT-AC68P⁽ⁿᵉʷ⁾. This guide is tested and working for many people and has been featured in LifeHacker. As this is a free resource please write questions in the comments below – do not call my business or use contact form.
All responsibility for anything that happens is yours.
- Update 12/23/2017: This guide has been rewritten past step 15 and old comments will reference the wrong steps. To see the original guide see this archived page.
- Update 3/23/2018: This guide has been altered to include AiMesh and AC68P flashing instructions.
How to flash AC1900 to AC68U:
- Install WinSCP, Putty, and a file archiver (click this link for ez). Install the Asus Restore Utility, mirror.
- Create a folder on your desktop, name it “router”.
- Download this file and extract it to the newly made router folder. It contains a firmware to downgrade to, a firmware to upgrade to, and mtd-write.
- Set static IP for PC.
start > run > ncpa.cpl > double click Ethernet > properties > IPV4 >
Subnet: Default (255.255.255.0)
- Place router into Recovery/Restore mode
Hold reset button 10 seconds
Power off router (keep holding reset)
Wait 10 seconds, keep holding reset
Power on router holding reset for 10 more seconds
- Go to 192.168.29.1 in a web browser
If Mini-CFE won’t load use Asus Restore Utility
- Flash TM-AC1900_22.214.171.124_376_1703-g0ffdbba.trx
- Wait for reboot <5 mins – WiFi lights will turn on when boot is complete
- Log in to router (admin:admin or admin:password)
- Go to Administration > System > Enable SSH > Yes > Apply
- Open Putty and WinSCP and connect them to 192.168.29.1 using a admin:admin or admin:password
Tip: In WinSCP select SCP as file protocol, in Putty SSH
- In putty type:
cat /dev/mtd0 > original_cfe.bin
- In WinSCP refresh the window on the right side and note that original_cfe.bin is present
- Copy original_cfe.bin to a local drive
- Upload original_cfe.bin to https://cfeditor.pipeline.sh/ > Select
126.96.36.199 US188.8.131.52 US for AC68P or 184.108.40.206 US AiMesh for AC68U with AiMesh as Source CFE > Download the new .bin > rename it to new_cfe.bin
- Upload new_cfe.bin & mtd-write & FW_RT_AC68U_30043763626.trx to router through WinSCP
- In Putty type:
chmod u+x mtd-write
- In Putty type:
./mtd-write new_cfe.bin boot
- In Putty type:
mtd-write2 FW_RT_AC68U_30043763626.trx linux
- Perform NVRAM Reset, wait for reboot <5 mins
a. Power off router
b. Wait 10 seconds
c. Press and hold WPS button
d. Power up the router and continue to hold WPS button for 15-20 seconds
- Reset PC IP back to default
- Log in to router using 192.168.1.1 and the router is now an AC68U with 64MB jffs
- Enable SSH and execute the code for fixing MD5 partition that is listed below.
- You can now flash Asus, Merlin, Advanced Tomato, Tomato, and DD-WRT firmwares.
Code for fixing MD5 partition so you can update to latest firmware:
(this is entered in Putty after enabling SSH on the router)
cat /dev/mtd5 > /jffs/mtd5_backup.bin
mount -t jffs2 /dev/mtdblock5 /tmp/asus_jffs
rm -rf /tmp/asus_jffs/*
sync && umount /tmp/asus_jffs
rm -rf /jffs/.sys/RT-AC68U
nvram unset fw_check && nvram commit && reboot
- Snbforums.com flash instructions: flashInstructions_cDec04_16.pdf
- Bootymonger from slickdeals: slickdeals.net
- Wherever I found https://cfeditor.pipeline.sh/
- Comment from Albert Lee (thanks!)
- If you have a fast connection you may benefit more from Merlin or official builds as they have enabled hardware acceleration which allows the router to download and upload at higher speeds.
- You may check router cpu speed at http://192.168.1.1/Tools_Sysinfo.asp
- If the 30/30/30 reset doesn’t work try this:
1. power off device
2. hold reset 20 seconds
3. power on device holding reset until power light blinks slowly
- If you can’t get Mini-CFE or Asus Restore utility to work try the method outlined in this comment: https://www.bayareatechpros.com/ac1900-to-ac68u/#comment-5679