5D2 help, is this thing toast?

I was out last night, taking some night cityscape shots, after a few shots, my baby just up and stopped working. After one of the shots, i went to playback and view some shots, and the LCD was just blank. Turned it off and on, nothing. The top LCD screen shows no info. The back LCD just has like a black look, its on, just shows black, as opposed to just being black as in turned off, does my description make sense?

The battery is full, i swapped out CF cards, I swapped out the lens....nothing. When I put the card in, and then put the battery in, the little red light does pop on. But there is no "sensor cleaning" deal popping up. The screen just turns like a black/grey. I can push the info button and it will swap the screen from the black/grey to just off. I can hit the live view button and it clicks, but nothing happens. I can't reclick it to turn live view back off.

Does anyone have an idea?

It sounds like you need to do some thorough troubleshooting of every bit of stuff, then you may need to decide whether it's worth sending the camera in for some "work". It'll cost, it's up to you!

It sucks, but Crap does happen on occasion.
Sorry to hear about your luck.

This is exactly what happens when there is a bad or blown fuse on the DC/DC PCB board.
It could also be the main board but that usually never results in a "dead" camera (dead as in exactly what you described : LCD lights up, but blank/black. No info on top LCD. No info in VF. And no response (pic taking).

I would definitely start with replacing the time/date battery first and trying a new card, new/charged main battery, checking for Brent pounds in the card slot, etc.

But i am willing to bet your baby needs a trip to a canon repair center. (I HIGHLY recommend the Newport News VA location if you're on the east coast)

This will run you a minimum of $220. I know, they literally just did this exact repair on my mark ii and that is what it cost me, AFTER my CPS Gold discount!(i believe original price was ~$270ish)

Good luck!