Nissan Almera N16 CD reader converting to bluetooth

[AnthonyLB]

Hi guys so I am trying lately to fit a bluetooth module to the CD/ audio unit of my Almera N16 of 2004. However it isn't as easy as i thought, I would like to avoid buying a cd changer like this :https://www.carinterface.nl/en/blue...ce-audio-adapter-nissan-car-stereo_mn-bua-nis , so I bought a bluetooth module that is powered in 5V and i can connect it to my phone it outputs 3 pins with left right and ground if I connect a headset on it it works , so now I want to basicaly find the aux pins on our cd/audio unit , and ofcours i don't find it .
I attach two photos of the audio unit that i opened if it helps someone

 

[AnthonyLB]

Now i don't have a picture but on the other side of the 12 pin connector on the right that was not in use , and on which the cd changer are to be connected you have the following pins chg-L+ chg-L- chg-R+ chg-R- GND GND H/U-CHG CHG-H/U REQ and NC NC but I have to take a picture I will edit this post but from what i saw on picture of cd changers they are connected on chg-L+ chg-L- chg-R+ chg-R- GND and H/U-CHG CHG-H/U REQ whic for me makes sense because you have basically the + and - of left and right and then the transmission lines from the CD to the AUDIO unit both ways , also i don't know what is the REQ for , However I tryed to connect the positive pins left and right to the bluetooth module and the negative pins to the ground of the bt module , and it did not work even if i try to insert a cd to fool my audio unit into thinking a cd is inserted , the problem might be that my CD unit doesn't work any more and so it cannot read properly cds , so maybe it doesn't trigger properly the cd mode if i can say and so my audio unit switches back to radio ... I have to find a way to fool the audio unit into thinking it is reading a cd for good . Any advises ?