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Home >> Mazda >> 2019 >> 6 Signature >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> On-Board Diagnostics - Rear Body Control Module (RBCM) >> DTC B109E-87: Communication Error With Start Stop Unit >> Notes
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DTC B109E-87: Communication Error With Start Stop Unit: Notes

DTC B109E:87 (REAR BODY CONTROL MODULE (RBCM)) DETECTION CONDITION AND POSSIBLE CAUSE

Description Communication Error With Start Stop Unit
Detection condition
  • Rear body control module (RBCM) detects a communication error with the start stop unit for 10 times continuously.
Fail-safe Not applicable
Possible cause
  • Start stop unit connector or terminal malfunction
  • Rear body control module (RBCM) connector or terminal malfunction
  • Short to ground in wiring harness between rear body control module (RBCM) terminal 3B and start stop unit terminal 1Q
  • Short to power supply in wiring harness between rear body control module (RBCM) terminal 3B and start stop unit terminal 1Q
  • Open circuit in wiring harness between rear body control module (RBCM) terminal 3B and start stop unit terminal 1Q
  • Start stop unit malfunction
  • Rear body control module (RBCM) malfunction
G12237223Courtesy of MAZDA MOTORS CORP.