Electrical problems in BMW – simultaneous malfunction of radio and air conditioning display

BMW driver question

I have an electronic problem. My radio has stopped working manually – no response from the buttons, the steering wheel control works. In addition, the climatronic stopped displaying information to me – nothing can be set on it.

The question is whether it is a fuse or maybe some relay and where to look for them possibly?

The problem was with the BMW 3 F30 touring, but it may also happen in other models.

Response from BM Cars service

The described problem is related to the functioning of the CIC (Car Information Computer) module in connection with the MOST bus (fiber optic bus).

We have too little data to determine the actual cause of the malfunction. Usually, the lack of response to the radio and “climatronic” control panel is related to the functioning of the panel itself or the suspension of the MOST bus operation. All its components are connected in series. Failure of any of the components causes suspension of the operation of the bus manifested as:

• lack of audio,
• dimming of the monitor,
• lack of response to the operation of iDrive,
• lack of response to the operation of the climatronic panel.

The fault is not related to a blown fuse or relay. A thorough search for the cause requires a full diagnostic of the vehicle. In particular, it is necessary to trace the elements of the MOST bus and its components.

Making an accurate diagnosis requires a visit to the service center. We invite you to visit at a convenient time.

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