"Who is ignorant about the 4 noble Truths in the beginning of
dependent origin co-arising when there was no self or consciousness?"
You were ignorant.
Being ignorant, you created self.
Being ignorant, you created consciousness.
"How can ignorance exist without consciousness ?"
It cannot.
Where there is ignorance, there is consciousness.
Where there is wisdom, there is no consciousness.
It's because you don't know what is consciousness, that you are bewildered by my answer.
And what is consciousness?
It's a fabrication. It's made up. It's fabricated with mental and physical activities. That is consciousness.
It is you fabricating this consciousness.
Now ask yourself, who is that "you" that I'm referring to in my answer?
No matter where you'd look, you would not find this "you".
So, who is ignorant if there is no "you" that can be found?
You is ignorant.
It's because you don't know who you are, that you are bewildered by my answer.
Find out who you are. Meditate. You will not find this "you". It's when not being able to find this "you", that you are seeing who you are. Once you see, examine how it works and truth will be realized: from ignorance arises fabrications, from fabrications consciousness, from consciousness birth, etc.