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Home >> Subaru >> 2016 >> BRZ Series.HyperBlue >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Engine Immobilizer System (W/ Entry & Start) >> Engine Immobilizer System (With Entry & Start System) >> DTC B278D ID Code Box Recognition Error >> Circuit description
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Circuit description

When the collation ECM (smart key ECM assembly) detects the input signal that indicates that the ID code box is installed on the vehicle even when ID code box is not registered, the collation ECM (smart key ECM assembly) outputs this DTC.

DTC DETECTION CONDITION

Diagnostic codes Detecting conditions Faulty part Diagnostic code output check operation
B278D Even without installation of the wire harness that judges whether the ID code box is installed on the vehicle or not, the collation ECM (smart key ECM assembly) receives the LIN signal from the ID code box. There are not the communication failure without ID code box. Always

*: Output only when a failure is noted.

Vehicle status and failsafe upon failure detection

VEHICLE STATUS AND FAILSAFE UPON FAILURE DETECTION

Vehicle status when a problem is detected Failsafe function when a problem is detected
Key registration is prohibited. -

[Current Data Display & Save]/[System Operation Check Mode]

DIAGNOSTIC TROUBLE CODE CHART

Diagnostic codes [Current Data Display & Save]/[System Operation Check Mode]
B278D -