With Position Memory System: Outline

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DTC B1038:13 [DASH-ELECTRICAL SUPPLY UNIT (US)] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Seat warmer unit (LH) circuit malfunction (Thermistor side)
Detection condition	The dash-electrical supply unit detects an open circuit in the seat warmer unit (LH) circuit.
Fail-safe	Stops the driver and front passenger's seat warmer output.
Possible cause	Seat warmer control unit connector or terminal malfunction Front seat (LH) malfunction Open circuit in any of following seat warmer unit (LH) circuits: Signal circuit Ground circuit Seat warmer unit (LH) malfunction Seat warmer control unit malfunction Dash-electrical supply unit malfunction
Courtesy of MAZDA MOTORS CORP.