DTC B1A21-13: Fm Antenna Amplifier Signal Circuit Malfunction [Connectivity Master Unit]: 4SD: Outline

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DTC B1A21:13 (CONNECTIVITY MASTER UNIT) DETECTION CONDITION AND POSSIBLE CAUSE (4SD)

System malfunction location	FM antenna amplifier signal circuit malfunction
Detection condition	The remote tuner (RT) detects an open circuit in the FM antenna amplifier signal circuit or a disconnection with the FM antenna amplifier for 2 s.
Fail-safe	Not applicable
Possible cause	Remote tuner (RT) connector or terminal malfunction FM antenna amplifier feeder malfunction Open circuit in FM antenna amplifier signal circuit FM antenna amplifier malfunction Remote tuner (RT) malfunction
Courtesy of MAZDA MOTORS CORP.