5D Mkii stuck at firmware update program when battery is inserted.

[OneCameraDude]

so I recently got a friend broken 5D Mkii. the problem is the second i insert the LP-E6N battery it jumps to life and goes into the firmware update firmware and when i attempt to update it, it goes to 99% or sometimes 23% and pops up "Update file error. Please check the memory card and reload the battery and try again." i can't access the menu or anything, im stuck in it and i tried everything. my friend never used magic lantern but i been on other forums and asked canon collectives, etc and im at a lost. i tried everything to different CF cards/batterys to pulling the thing apart to see if something was lose or missing on the logic board. i tried looking for older firmwares since the original firmware is 1.0.7 trying to update to firmware 2.1.2 but i had no luck in finding anything. i even tried putting magic lantern on it even tho the firmware isn't 2.1.2 but i got one flash on the LED and a black screen. im at the point thinking it's a logic board issue or something. please help, thank you in advance

[Walter Schulz]

Use a card > 32 GByte or use partitioning software to create a smaller partition using FAT32.
Copy firmware file 2.1.2 and try to close update cycle.
If unlucky: Use Web Archive Wayback Machine and browse archived versions of Pelican's repository (www.pel.hu/eoscard). Delete other firmware versions from card and retry with older versions.
Report results.

[OneCameraDude]

the 1st thing you said didn't work. HOWEVER the second one with using the Archive has worked and i got it working on 1.0.7 and have updated to 1.1.0 HOWEVER i ran into a few problems. i keep getting a error 70 when taking a photo sometimes and is really annoying because i might miss that shot, i tried different CF cards and the 2nd problem is that i can't update to 1.2.4 or anything higher. so the camera says it's on 1.1.0 however when i go into the update program, it says "current version 1.0.7" when it supposed to be on 1.1.0. i tried updating to 1.2.4 but the link you gave me the 1.2.4 file was corrupted but i found another one and tried updating but it ended up bricking the camera again and i had to go back onto 1.0.7 or 1.1.0.

there's also another weird issue when i turn the camera off and turn it back on, it resets SOME of my settings like video format and LCD brightness and the most annoying, it resets my picture settings. tho it keeps the clock and date and my other settings, i replaced the clock battery (which was almost dead anyway) but i still get these issues. i want to update to the latest but i need the firmware update problem to say it's on 1.1.0 instead of 1.0.7 so i can update in order.

[Walter Schulz]

Reinstall 1.0.7.
Reset camera defaults. Including Fn settings.
Install 2.1.2 (it is not necessary to go through all firmware updates. Firmware files are comulative and contain all fixes coming with older firmware versions)

[OneCameraDude]

I tried what you said Walter. I installed 1.0.7 then clear every setting and FN settings and tried to install 2.1.2 sadly the update failed (update file error)  and went into the bricked state again so I had to go back on 1.0.7/1.1.0.

[Walter Schulz]

Sorry, above my pay grade. Maybe a1ex may have a word or two.

[a1ex]

At this stage, it's probably best to look at Canon's debug messages to see why exactly it fails.

Easiest way: UART.

Software-only solution for logging Canon messages during a firmware update is also possible, but may require a few days of work. Unable to allocate this time atm, sorry.

there's also another weird issue when i turn the camera off and turn it back on, it resets SOME of my settings like video format and LCD brightness and the most annoying, it resets my picture settings.

This one could give some clues. Video format is on the MPU side (this list), but LCD brightness is not. Most picture settings (image quality, picture style etc) are also saved on the MPU side. Messages printed on UART during normal operation could be useful, too.

I can capture these messages, with various degrees of verbosity, but only on 2.1.2. Other firmware versions require significant work.

[yourboylloyd]

I would just take it to canon at this point.

[OneCameraDude]

i try to give it a shot. the reason im not taking it to canon yet is because im a broke teenager with not alot of money on hand rn.

[reddeercity]

Just encase here the 2.12 firware from canon eos5d2-v212-win.zip
You say you formatted the cf card , was that in camera or in a cf card reader ? if you you did format in the card reader was it a "Quick format" or a "Low level format"
and did you have the the Lens attacked ?
I search with google came back with a few people having problems the same as you , some had cf card format problems , others had incomplete
exaction of the firmware zip file and a few with Lens "error70"communication problem .

here is the Canon firmware updating procedure 5d2-firmwareupdate-en.pdf
There stuff even I didn't know in there ,
Here a quick over view of the firmware updating  procedure

1)Fully Charged Battery or AC Adapter
2)CF Cared (64MB or more, or 64GB orLess)
3)Exact firmware to temp dir on computer hard drive
check the firmware file size in bytes , right click on file
(file name: 5D200212.FIR, file size: 9,754,668 bytes)
4)format card in camera (should work in card reader also , but canon wants it in camera I guess to make sure it's FAT32.
5)copy firmware (5D200212.FIR) to root of the card (not in any sub-directory)
6)Rotate the Mode Dial to select "P" Mode
7)Insert CF card with firmware in the root of the card
8)Turn Power Swith to "On" position  , the first click , then press menu go to firmware update etc. .....

You can also use the EOS Utility to update the firmware also , the procedure is in the linked pdf file
Made sure there's not bent pins in camera for cf card or your card reader
Canon say's nothing about the Lens being attached or not but i would try without it right now .

Hope this helps