ENTRY AND START SYSTEM(for Entry Function), Diagnostic DTC:B27A7

DTC Code	DTC Name
B27A7	Open in Inside Luggage Compartment Electrical Key Oscillator Circuit

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 2 indoor electrical key antenna assembly (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. 2 indoor electrical key antenna assembly (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. 2 indoor electrical key antenna assembly (inside luggage) (CLG7 - ANTE7, CG7B - CLGB) (1 trip detection logic*1).	Harness or connector No. 2 indoor electrical key antenna assembly (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 power 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

WIRING DIAGRAM

CAUTION / NOTICE / HINT

Note

When using the GTS with the vehicle power switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry & Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
The entry and start system (for Entry Function) uses a LIN communication system and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting Click here. Troubleshoot the entry and start system (for Entry Function) after confirming that the communication systems are functioning properly.
Before replacing the certification ECU (smart key ECU assembly), refer to the entry and start system (for Entry Function) precaution Click here.
After repair, confirm DTC does not reoccur by performing the "DTC Output Confirmation Operation".
No. 2 indoor electrical key antenna assembly (inside luggage) has an antenna coil between ANTE7 and CLGB terminals.

PROCEDURE

CHECK CONNECTOR CONNECTION CONDITION
1. Turn the power switch off.
2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and the No. 2 indoor electrical key antenna assembly (inside luggage).
  
  OK
  
  Connectors are properly connected.
NG
CONNECT CONNECTORS PROPERLY

OK

OK
Connectors are properly connected.

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE))

Disconnect the F46 and F48 certification ECU (smart key ECU assembly) connector.
Disconnect the K10 No. 2 indoor electrical key antenna assembly (inside luggage) connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
F46-4 (CLG7) - K10-1 (ANTE7)	Always	Below 1 Ω
F46-3 (CG7B) - K10-3 (CLGB)	Always	Below 1 Ω
F48-1 (E) - Body ground	Always	Below 1 Ω
F46-4 (CLG7) - Body ground	Always	10 kΩ or higher
F46-3 (CG7B) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE))

Text in Illustration
*a	Component with harness connected (Certification ECU (smart key ECU assembly))	*b	Waveform
*c	Door open	*d	After approximately 30 seconds from when the door is closed

Reconnect the F46 and F48 certification ECU (smart key ECU assembly) connector.
Reconnect the K10 No. 2 indoor electrical key antenna assembly (inside luggage) connector.

Using an oscilloscope, check the waveform.

Tech Tips

Check that the customizing "Ignition Available Area" setting of entry and start system is All Click here.

Tester Connection

Switch Condition

Tool Setting

Specified Condition

F46-4 (CLG7) - F48-1 (E)

Procedure:

Power switch off
Electrical key transmitter sub-assembly not inside vehicle
Door is open
Door is closed
Within 30 seconds

2 V/DIV., 500 ms/DIV.

Pulse generation

(See waveform)

F46-3 (CG7B) - F48-1 (E)

Procedure:

Power switch off
Electrical key transmitter sub-assembly not inside vehicle
Door is open
Door is closed
Within 30 seconds

2 V/DIV., 500 ms/DIV.

Pulse generation

(See waveform)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPLACE NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE)
1. Temporarily replace the No. 2 indoor electrical key antenna assembly (inside luggage) with a new or normally functioning one Click here.
NEXT
CHECK DTC OUTPUT
1. Clear the DTCs Click here.
2. Recheck for DTCs Click here.
  
  OK
  
  B27A7 is not output.
OK
END (NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE) WAS DEFECTIVE)

NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)