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DTC B109E-87: Communication Error With Start Stop Unit: Notes

WARNING: This page is about a different car, the 2016 Mazda CX-3. However, it is still accessible from the selected car via links, so may be relevant.
Description  Communication error with start stop unit
Detection condition 
  • BCM detects a communication error with the start stop unit for 10 times continuously  with the ignition switched ON (engine off or on).
Fail-safe  Not applicable
Possible cause 
  • Start stop unit connector or terminal malfunction
  • BCM connector or terminal malfunction
  • Short to ground in wiring harness between start stop unit terminal 1Q and BCM terminal 2J
  • Open circuit in wiring harness between start stop unit terminal 1Q and BCM terminal 2J
  • Start stop unit malfunction
  • BCM malfunction
G10913662