If the manas were separated from the particular wisdom of the mind consciousness, would it then be without any activity?

Let us look at concrete examples of situations without the mind consciousness, and we will know the answer to this question. Situations without the mind consciousness include, for example, when one is asleep without dreams and when one is dreaming. At such times, what is the manas doing? Is it idle and unoccupied, not contacting sense objects, not discerning states of experience? Clearly not. Because at all times, the tathāgatagarbha gives rise to and manifests all dharmas, and the manas has the characteristic of silently encompassing all dharmas; He will certainly rely on the tathāgatagarbha to contact the dharmas that the tathāgatagarbha has secondarily transformed and illusorily produced, taking the dharmas seen by the tathāgatagarbha as what He Himself sees, and taking these dharmas as His own possessions, thereby giving rise to all kinds of mental activities and thoughts, to the point of causing dreams to appear. All the thoughts and concepts in a dream belong to the manas, all mental activities belong to the manas, and the mind consciousness only plays a role in assisting the manas. Therefore, how a person is truly progressing in practice depends on his performance in dreams.

When one is unconscious, there is no mind consciousness, yet the manas is not resigned to remaining in that unconscious state; when it finds that the body has improved slightly, it will struggle to wake up. This shows that when the manas is unconscious without the mind consciousness, it has mental activity; all the mental factors (caittas) are operating, constantly paying attention to the condition of the body faculty (kāya-indriya), able to discern the state of the body faculty, knowing that being unconscious is not good, and also finding ways to wake up. Some people, while unconscious, will even seek out those close to them to rescue themselves, transmitting information, telling those close to them where they are and what their situation is. Therefore, the manas can represent an independent person, possessing various mental activities and mental factors, with much inner activity; it is merely that when it operates, it needs the mind consciousness and the five sense consciousnesses to cooperate in order to complete the task.