DTC B1520-87: Communication Error With Front Seat Warmer Control Unit

B1520:87 (DASH_ESU) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Communication error with front seat warmer control unit
Detection condition	The dash-electrical supply unit cannot receive the signals from the position memory control module/front seat warmer control unit/front seat ventilation control unit.
Fail-safe	Stops the driver and front passenger's seat warmer output. Inhibits the seat position recall and seat position programming of the position memory system.
Possible cause	Malfunction in wiring harness (including connector/terminal) between position memory control module/front seat warmer control unit/front seat ventilation control unit and dash-electrical supply unit (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Position memory control module/front seat warmer control unit/front seat ventilation control unit malfunction (Refer to [POSITION MEMORY CONTROL MODULE REMOVAL/INSTALLATION ] ). (Refer to [FRONT SEAT WARMER CONTROL UNIT (LH) REMOVAL/INSTALLATION ] ). (Refer to [FRONT SEAT WARMER CONTROL UNIT (RH) REMOVAL/INSTALLATION ] ). Dash-electrical supply unit malfunction (Refer to [DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION ] ).
Repeatability verification procedure	Clear the DTC recorded in the memory. (See CLEARING DTC .)
Courtesy of MAZDA MOTORS CORP.
1	Dash-electrical supply unit
2	Vehicles with position memory system  Position memory control module/front seat warmer control unit/front seat ventilation control unit Vehicles without position memory system  Front seat warmer control unit/front seat ventilation control unit