I bought an Audi Q5 Quattro 2.0 since 2009 and most of the MST or MMI component has failed (knowing that the system is no longer functioning if a component is defective). Please recommend the documentation (video) of the structure and location of the MMI components (navigation, phone, sound system, CD, etc.) so that I can check which ones are faulty by buying a fiber most optically and eliminating , in turn, the components. I am not specialized in this field. Thank you in advance.