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DTC B2278: Engine Switch Circuit Malfunction: Description

This DTC is stored when 1) a malfunction is detected between the power source control ECU and the engine switch; or 2) either of the switches inside the engine switch is malfunctioning.

HINT: 

When the power source control ECU is replaced with a new one and the cable from the negative (-) battery terminal is connected, the power source mode becomes IG-ON mode. When the battery is removed and reinstalled, the power source mode that was selected when the battery was removed is restored.

DTC No. DTC Detection Condition Trouble Area
B2278 Communication is abnormal between the power source control ECU and engine switch or the engine switch is defective
  • Engine switch
  • Power source control ECU
  • Wire harness or connector
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