With Position Memory System: Outline

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DTC B103A:11 [DASH-ELECTRICAL SUPPLY UNIT (US)] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Seat warmer unit (RH) circuit malfunction (Thermistor side)
Detection condition	The dash-electrical supply unit detects a short to ground in the seat warmer unit (RH) circuit.
Fail-safe	Stops the driver and front passenger's seat warmer output.
Possible cause	Seat warmer control unit connector or terminal malfunction Connector C-62 malfunction Short to ground in seat warmer unit (RH) signal circuit Front seat (RH) malfunction Seat warmer unit (RH) malfunction Seat warmer control unit malfunction Dash-electrical supply unit malfunction
Courtesy of MAZDA MOTORS CORP.