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DTC B27A9: Open in Floor/Extra Electrical Key Oscillator Circuit [09/2016 - 05/2019]: Description

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 2 electrical key antenna (extra antenna). For the No. 2 electrical key antenna (extra antenna) to detect when the electrical key transmitter sub-assembly is brought close to the vehicle, the received request signal is transmitted within approximately 1 m (3.28 ft.) of the charging port lid. DTC B27A9 is stored by the certification ECU (smart key ECU assembly) when an open is detected between the certification ECU (smart key ECU assembly) and No. 2 electrical key antenna (extra antenna) (between terminals CLGP and CLG, or terminals CGPB and CLGB).

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B27A9 Open in Floor/Extra Electrical Key Oscillator Circuit An open is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 2 electrical key antenna (extra antenna) (CLGP - CLG, CGPB - CLPB) (1 trip detection logic*).
  • Certification ECU (smart key ECU assembly)
  • No. 2 electrical key antenna (extra antenna)
  • Harness or connector
DTC Output Confirmation Operation: 
  1. Any time
  1. *: Only output while a malfunction is present and the power switch is on (IG).
VEHICLE CONDITION AND FAIL-SAFE OPERATION WHEN MALFUNCTION DETECTED

Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Charging port lid cannot be unlocked -
RELATED DATA LIST AND ACTIVE TEST

DTC No. Data List and Active Test
B27A9 Key diagnostic mode can be used to perform troubleshooting