ENTRY AND START SYSTEM(for Start Function), Diagnostic DTC:B27A5

DTC Code DTC Name
B27A5 Open in Front Floor Electrical Key Oscillator Circuit

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 1 indoor electrical key antenna assembly (front floor). For the No. 1 indoor electrical key antenna assembly (front floor) to detect when the electrical key transmitter sub-assembly is in the cabin, the signal from the certification ECU (smart key ECU assembly) requesting a response from the electrical key transmitter sub-assembly is transmitted inside the vehicle. DTC B27A5 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. 1 indoor electrical key antenna assembly (front floor) (between terminals CLG5 and ANTE5, or terminals CG5B and CLGB).

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B27A5 Open in Front Floor Electrical Key Oscillator Circuit An open is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (front floor) (CLG5 - ANTE5, CG5B - CLGB) (1 trip detection logic*).

  • Certification ECU (smart key ECU assembly)

  • No. 1 indoor electrical key antenna assembly (front floor)

  • Harness or connector

    DTC Output Confirmation Operation:

  • Any time

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected

When electrical key transmitter sub-assembly is in front seat area:


  • Power source mode does not change when power switch pressed

  • Electrical key transmitter sub-assembly locked inside vehicle

 -
Related Data List and Active Test
DTC No. Data List and Active Test
B27A5 Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

B000PGKE21

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the power switch off, connect the GTS to the DLC3 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 Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start. 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 Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the entry and start system (for Start Function) after confirming that the communication systems are functioning properly.

    Click here

  • Before replacing the certification ECU (smart key ECU assembly), refer to the Service Bulletin.

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

PROCEDURE


  1. CHECK CONNECTION OF CONNECTOR


    1. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (front floor).

      Result
      Result Proceed to
      The connectors are properly connected A
      The connectors are not properly connected B

    B

    CONNECT CONNECTORS PROPERLY

    A

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR))


    1. Disconnect the P66 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the P37 No. 1 indoor electrical key antenna assembly (front floor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      P66-8 (CLG5) - P37-1 (ANTE5) Always Below 1 Ω
      P66-9 (CG5B) - P37-3 (CLGB) Always Below 1 Ω

    4. Reconnect the P66 certification ECU (smart key ECU assembly) connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR))

    B000SIZC09
    *a

    Component with harness connected

    (Certification ECU (Smart Key ECU Assembly))

    		 *b Waveform
    *c For 30 seconds after any door closed *d After 30 seconds or more have elapsed since any door closed

    1. Using an oscilloscope, check the waveform.

      OK
      Tester Connection Condition Tool Setting Specified Condition
      P66-8 (CLG5) - P66-18 (E)

      Procedure:


      1. Power switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. Within 30 seconds of closing any door

      		 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)
      P66-9 (CG5B) - P66-18 (E)

      Procedure:


      1. Power switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. Within 30 seconds of closing any door

      		 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR) Click here

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)