DTC B27A7: Open in Inside Luggage Compartment Electrical Key Oscillator Circuit [03/2017 - ]: Description

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 3 indoor electrical key oscillator (inside luggage). For the certification ECU (smart key ECU assembly) to detect when the key is inside the luggage compartment, the signal from the certification ECU (smart key ECU assembly) requesting a response from the key is transmitted inside the luggage compartment. DTC B27A7 is stored by the certification ECU (smart key ECU assembly) when an open circuit is detected between the certification ECU (smart key ECU assembly) and No. 3 indoor electrical key oscillator (inside luggage) (between terminals CLG7 and ANTE7, or terminals CG7B and CLGB).

DTC No.	DTC Detection Condition	Trouble Area	DTC Output Confirmation Operation
B27A7	An open circuit is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 3 indoor electrical key oscillator (inside luggage) (CLG7 - ANTE7, CG7B - CLGB) (1 trip detection logic*1).	Wire harness or connector No. 3 indoor electrical key oscillator (inside luggage) Certification ECU (smart key ECU assembly)	Any time*2

*1: Only output while a malfunction is present.
*2: Only when the vehicle is stopped.

VEHICLE CONDITION AND FAIL-SAFE OPERATION WHEN MALFUNCTION DETECTED

Vehicle Condition when Malfunction Detected	Fail-safe Operation when Malfunction Detected
When key is in luggage compartment: Power source mode does not change when engine switch is pressed Key becomes locked inside vehicle	-

RELATED DATA LIST AND ACTIVE TEST

DTC No.	Data List and Active Test
B27A7	Key diagnostic mode can be used to perform troubleshooting