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DTC B2278: Engine/Power Switch Malfunction [10/2018 - ]: Description

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This DTC is stored when the SSW1 contact signal and SSW2 contact signal, which are detected when the power switch is operated, do not match.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B2278 Engine/Power Switch Malfunction When the power switch is operated, the SSW1 contact signal and SSW2 contact signal do not match (1-trip detection logic*).
  • Power switch
  • Certification ECU (smart key ECU assembly)
  • Wire harness or connector
 DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG).
  1. *: Only detected while a malfunction is present.
VEHICLE CONDITION AND FAIL-SAFE FUNCTION WHEN MALFUNCTION DETECTED

Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected
If either the SSW1 contact signal or SSW2 contact signal is stuck on, the power source mode cannot be changed by pressing the power switch. If either the SSW1 contact signal or SSW2 contact signal is stuck off, emergency stop by pressing and holding the power switch for 2 seconds or more cannot be operated. -
RELATED DATA LIST AND ACTIVE TEST ITEMS

DTC No. Data List and Active Test
B2278 Power Source Control 
  • Start Switch1
  • Start Switch2
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