My take has always been that the Bio-monitor was a mislabeling of the Auto senses as that's the only thing that makes sense. 

The RAW also has you add or subtract one from the rolls on the history tables. If you roll parts of the same mark as your base armour you just don't pick that one(unless you just don't want to have any effect from the history.)

 Regarding Wolf Senses...

Wolf Senses specifically states that it must be used in Solo Mode, in the core rulebook. It is a Solo Ability, yes, and in its description says it must be used in Solo Mode.

However, on using Solo Modes in Squad Mode, Rites of Battle uses Wolf Senses as an example of using a Passive Solo Mode ability in Squad Mode for no cost in Cohesion.

Which is correct? I would assume Rites of Battle, since it is later, and a Space Wolf likely doesn't lose his ability to see in the dark because of teamwork.

 Rites of Battle is correct, as it is a clarification of the Core Rules. Passive Solo Mode Abilities can be used for free in Squad Mode.

Gaire said:

I know that, yes, as it clarifies how Solo Mode abilities work. However, it does not clarify the text in the Wolf Senses ability, which is the only ability which specifically states that the Space Wolf must be in Solo Mode. For instance, the Ultramarines ability, which is Passive too, does not state this. That means that it can be used in Squad Mode. 

Like I said, I lean towards your interpretation, but it specifically says otherwise.

 That statement in the Core book about Wolf Senses only being usable in Solo Mode is overridden by the rules in Rites of Battle. Look at it logically: why would suddenly working as part of a team remove a Space Wolf's ability to perceive things incredibly well?

 I know that. I know that it makes perfect sense for it to work in Squad Mode. Regardless, Rites of Battle does not say to remove the text in the Core Rulebook saying that Wolf Senses applies when 'the Space Wolf is in Solo Mode'.

This has not been clarified in errata, and it is why I am asking. I am not asking for a favourable interpretation, I am asking for an actual clarification. I am asking about the rules, not about common sense. As it is written, it's rather clear that Wolf Senses cannot be used in Squad Mode. The correct interpretation is obviously the opposite, but to many people, that isn't good enough (especially those that aren't native English speakers, for example).

It's realy very simple. The core book didn't have active or passive solo modes. You couldn't use any of them while in squad mode.

Rites of Battle intruduced the distinction between them and included a list. Wolf Senses is listed as passive. This means you can use it in squad mode freely.

Nathiel said:

It doesn't say 'ignore the text in the Wolf Senses ability', although it should. It is listed as Passive, which could be interpreted as you not being allowed to spend Cohesion to use it when in Squad Mode. Also, it could be listed as Passive for future reference, even though it can't be used in Squad Mode.

RoB P 225 - "Passive Solo Mode abilities function as normal when in Squad Mode. The Space Marine has free use of them at all times."

 the one thing i wish to say directly to FFG… DONT YOU MESS WITH MY BOLT WEPONS!!!! also i didnt agree with the decress in the damage of the rites of battle melee stuff but he AP incress i agree with. the melta bost was much needed thank the emperor! over all not much to gripe about witch shows they did a good job.

Nathiel said:

Correct, they have free use at all times. However, a part of the power says that it can't be used in Squad Mode. You can, according to the Passive/Active rules, use it. However, that does not supersede the power's text itself.

For example, if a power gave you Tearing with all weapons, when in melee, and was Passive, could you use it when using a Bolter? No, even though you have free use at all times, the power's text is different.

I agree on the intent entirely, don't get me wrong, but the Errata/FAQ should cover this, especially for players who don't wish to purchase Rites of Battle.

Onyx Bana said:

Out of curiosity, was this redacted, or is there a newer errata link? I can't find any mention of that in the (as far as I know) current version of the errata. Any clarification would be appreciated, thanks.

Pyrus said:

No, it's still there. Keep in mind, this is discussing the Rites of Battle deed "Omnissiah's Calling" and not the core rulebook Techmarine.

Gaire said:

Ah, so it is. I don't know how I missed that. Thanks!

 I've got a question about the scolastic lore: codex astartes, is it an oversight that it is not a part of the ultramarines advances? It seems strange that the only ones that can advance normally on that skill is librarians and that the chapter that wrote the codex can not.