Problem: The customer’s concern was that the
radio worked one day and not the next. All of the radio lights
were on but no sound was coming from the speakers. There were no
Details: This radio is equipped with the MOST
(Media Oriented Systems Transport) bus network system. Any break
in the fiber-optic cable will cause this kind of issue. The MOST bus connector is located in
the trunk near the left rear seat above the wheel house. This
location is the best place to perform MOST system tests and to
see if light is present in all fiber-optic cables. In this case,
the technician found a mouse nest near the MOST bus connector and
one fiber optic line had sustained some mouse-inflicted damage.
Confirmed Repair: The shop bought a fiber optic
repair kit from a BMW dealer and fiber-optic crimping pliers to
repair the line. After the repairs, the radio worked normally and
sound was restored.