So i short circuited the fuse for BCM (#15) and the Brake Failure message disappeared ! So the problem is not the BCM but the CEM. Cheaper to fix but a pain to remove.

I just talked with them. Great guys! Likely the CEM and they gave me one more test to do before pulling it.
Thanks!

I have a new to me 2007 XC70 that came with:
Message:
- Brake Failure Stop Safely
- Park assist service required
- Engine maintenance required

I pulled the next level of DTC codes
- BCM NOT CHECKED
- SRS ready
- ECM DTC SET
- CEM DTC SET
and other DTC sets present

I checked the CEM and there is ...