ENTRY AND START SYSTEM (for Entry Function), Diagnostic DTC:B27A1

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the front door outside handle assembly (for driver door) [electrical key antenna] at intervals of 0.25 seconds. For the front door outside handle assembly (for driver door) [electrical key antenna] to detect when the electrical key transmitter sub-assembly is brought close to the vehicle, a signal requesting a response from the electrical key transmitter sub-assembly is transmitted within approximately 1 m (3.28 ft.) of the driver door at intervals of 0.25 seconds. DTC B27A1 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 front door outside handle assembly (for driver door) [electrical key antenna] (between terminals CLG1 and ANT1, or terminals CG1B and ANT2).

• *: Only output while a malfunction is present.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK CONNECTOR CONNECTION

   
   

   1. Turn the power switch off.

   2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and front door outside handle assembly (for driver door).

      OK
      Connectors are properly connected.

   
   

   NG

   CONNECT CONNECTORS PROPERLY

   OK

2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - FRONT DOOR OUTSIDE HANDLE ASSEMBLY AND BODY GROUND)

   
   

   • *1: for LHD

   • *2: for RHD

   
   

   1. Disconnect the N94 certification ECU (smart key ECU assembly) connector.

   2. Disconnect the Q23*1 or Q8*2 front door outside handle assembly (for driver door) connector.

   3. Disconnect the Q18*1 or Q3*2 front multiplex network door ECU connector.

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition N94-5 (CLG1) - Q23-6 (ANT1) Always Below 1 Ω N94-4 (CG1B) - Q23-3 (ANT2) Always Below 1 Ω N94-1 (E) - Body ground Always Below 1 Ω Q23-2 (GND) - Q18-11 (OSCE) Always Below 1 Ω N94-5 (CLG1) or Q23-6 (ANT1) - Body ground Always 10 kΩ or higher N94-4 (CG1B) or Q23-3 (ANT2) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition N94-5 (CLG1) - Q8-6 (ANT1) Always Below 1 Ω N94-4 (CG1B) - Q8-3 (ANT2) Always Below 1 Ω N94-1 (E) - Body ground Always Below 1 Ω Q8-2 (GND) - Q3-11 (OSCE) Always Below 1 Ω N94-5 (CLG1) or Q8-6 (ANT1) - Body ground Always 10 kΩ or higher N94-4 (CG1B) or Q8-3 (ANT2) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO DRIVER SIDE ELECTRICAL KEY ANTENNA)

   
   

   • *1: for LHD

   • *2: for RHD

   
   

   1. Connect the N94 certification ECU (smart key ECU assembly) connector.

      

      Text in Illustration

      *1	Waveform 1	*2	Waveform 2
      *a	Component with harness connected (Certification ECU [Smart Key ECU Assembly])	-	-

   2. Connect the Q23*1 or Q8*2 front door outside handle assembly (for driver door) connector.

   3. Connect the Q18*1 or Q3*2 front multiplex network door ECU connector.

   4. Using an oscilloscope, check the waveform.

      OK

      Tester Connection Switch Condition Tool Setting Specified Condition N94-5 (CLG1) - N94-1 (E) Procedure: Power switch off Electrical key transmitter sub-assembly brought outside vehicle All doors closed Electrical key transmitter sub-assembly not inside vehicle Electrical key transmitter sub-assembly brought inside detection area*1 All doors locked through wireless operation 2 V/DIV., 500 ms/DIV. Pulse generation (See waveform 1) N94-5 (CLG1) - N94-1 (E) Procedure: Power switch off Electrical key transmitter sub-assembly brought outside vehicle All doors closed Electrical key transmitter sub-assembly not inside vehicle Electrical key transmitter sub-assembly brought outside detection area*2 All doors locked through wireless operation 2 V/DIV., 500 ms/DIV. Pulse generation (See waveform 2) N94-4 (CG1B) - N94-1 (E) Procedure: Power switch off Electrical key transmitter sub-assembly brought outside vehicle All doors closed Electrical key transmitter sub-assembly not inside vehicle All doors locked through wireless operation 2 V/DIV., 500 ms/DIV. Pulse generation (See waveform 2)

      
      

      • *1: For details about the areas that are inside the entry function detection area, refer to Operation Check Click here.

      • *2: For details about the areas that are outside the entry function detection area, refer to Operation Check Click here.

   
   

   NG

   REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

   OK

4. REPLACE FRONT DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER DOOR)

   
   

   1. Temporarily replace the front door outside handle assembly (for driver door) with a new or known good one Click here.

   
   

   NEXT

5. CLEAR DTC

   
   

   1. Clear the DTCs Click here.

   
   

   NEXT

6. CHECK FOR DTC

   
   

   1. Check for DTCs Click here.

      OK
      DTC B27A1 is not output.

   
   

   NG

   REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

   OK

   END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY [FOR DRIVER DOOR] WAS DEFECTIVE)