Firmware update fails when using non-Canon battery.

[Euan]

This may be something that's well known, but I did a search and couldn't find any posts relating to this issue.

When I recently tried to install ML, I found my 5D would spend 5 seconds on the FW update screen before simply restarting without loading ML. I went through the obvious steps of reloading FW 2.1.2 and trying different CF cards. It turns out that the thing that was preventing ML from loading in the FW updater was the fact I was using cheap, nasty, third party batteries. As soon as I put a Canon one in, I was able to load ML.

It might be worth making a note of this in the Troubleshooting section of the INSTALL.pdf. That is, unless it's only me who's encountered the issue.

[Francis]

Moving to general Q&A, as this is not a bug. I don't believe you can update Canon firmware without a chipped battery or AC adapter either.