With Bose® and 4SD: Outline

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DTC B1A05:2B (CONNECTIVITY MASTER UNIT) DETECTION CONDITION AND POSSIBLE CAUSE - WITH BOSE® AND 4SD

System malfunction location	Rear center speaker audio output circuit malfunction
Detection condition	The audio amplifier detects a short circuit between the rear center speaker audio output circuits for 30 s.
Fail-safe	Not applicable
Possible cause	Rear center speaker connector or terminal malfunction Audio amplifier connector or terminal malfunction Rear center speaker malfunction Short circuit between rear center speaker audio output circuits Audio amplifier malfunction
Courtesy of MAZDA MOTORS CORP.