FritzBox 4040 installation

I'm new to OpenWrt but I would like to do my first steps by flashing OpenWrt to my FritzBox 4040. The currently provided information is a bit confusing for me, so I'm asking for help here:

There is no device page for the FB 4040 yet, that's not good for me when doing my first steps. But I had a look on the techdata page and it is stated there, that the stock bootloader is not supported and one needs to use U-Boot instead. I found first instructions for that on the forum. On the other hand, the last comment there by @craz sounds as if there is a new EVA image now, which is easier to flash. One of the git commits affecting this device supports that assumption.

Can someone tell me if the "Stock bootloader unsupported, U-Boot must be installed" information is outdated and how to properly flash the FB 4040?

It kinda is.

So you could download the eva.bin images from the 18.06.1 release to your PC:

and grab the latest script from:

Then, you need to connect your PC to one of the yellow LAN ports and set ethernet to static IPv4 address between and and execute the script
at the "right time":

# sh openwrt-18.06.1-ipq40xx-avm_fritzbox-4040-squashfs-eva.bin

after you powered on the FritzBox 4040. It will run for 2+ minutes (erasing, flashing and verifying the data takes time) and once you see the

150 Flash Check 0x... 

you can wait a few more seconds and just power-cycle the router or issue the reboot command manually through a separate ftp shell. On the following boot, the device should be running OpenWrt (The 18.06.1 comes with a webui/Luci on or you can ssh into the device via - don't forget to change back your ethernet to dhcp or some static address in the address (I think the standard subnetmask is /24 ) - to setup and enable the WiFis there)

Note: The "right time" is somewhere between 5 seconds to 30-45 seconds after a hard power-on (i.e.: when the box starts to reply to pings to If the script just fails with "Fritzbox at is not reachable (yet)." Just start it again.)

1 Like

Just to say that 18.06.1 is very stable on this router, now I have 36 days of uptime.

Once you have switched to openwrt you must change the ath10k firmware as written here because no one has modified it in the 18.06 branch:

Thanks, flashing worked flawlessly.

Regarding the ath firmware, I will take a look once I got an internet connection.;a=commit;h=0a492ee39e1c1a226dc34923909459117077b4c5 seems to address some ath firmware issues.

This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.