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DTC B278C: Lost Communication with Power Source Control [04/2013 - ]: Description

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This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and power management control ECU stops for 10 seconds or more.

DTC No. Detection Item DTC Detection Condition Trouble Area
B278C Lost Communication with Power Source Control An internal malfunction occurs in the certification ECU (smart key ECU assembly). Certification ECU (smart key ECU assembly)

HINT: 

The power management control ECU is built into the certification ECU (smart key ECU assembly).