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DTC B1C84 12: Rear Window Defroster Relay Circuit Malfunction: Notes

DTC B1C84 12 DETECTION CONDITION AND POSSIBLE CAUSE

Description  Rear window defroster relay circuit malfunction 
Detection condition 
  • Front body control module (FBCM) detects a short to power supply in the rear window defroster relay circuit with the ignition switched ON (engine off or on).
Fail-safe function  Not applicable
Possible cause 
  • Rear window defroster relay malfunction
  • Front body control module (FBCM) connector or terminal malfunction
  • Short to power supply in wiring harness between rear window defroster relay terminal E and front body control module (FBCM) terminal 1P
  • Front body control module (FBCM) malfunction
G09771804Courtesy of MAZDA MOTORS CORP.