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Audio System - Radio Switches From Stereo to Mono

SI B 65 05 05
Sound System, Cruise, Alarms, Monitors

July 2005
Technical Service

This Service Information Bulletin supersedes Measure B65 209 04 dated 04/30/2004.

SUBJECT
BM53 Radio is Switching from Stereo to Mono

MODEL
E46 (3 Series) with Navigation system and Harman-Kardon sound system, from September 2001 on

E39 (5 Series) with Navigation system and DSP (Digital Sound Processor), from September 2001 on

E53 (X5) with Navigation system and DSP, from October 2001 on

SITUATION

In FM mode only, the radio sound is switching from stereo to mono, fading in and out.

CAUSE

Switch over threshold is too sensitive in the BM53 Radio.

CORRECTION

If the complaint is reproducible, install a BM53 radio with the improved software for the switch over threshold.





PARTS INFORMATION





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