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DTC B27A7: Open in Inside Luggage Compartment Electrical Key Oscillator Circuit: Procedure

  1. CHECK CONNECTOR CONNECTION CONDITION 
    1. Turn the engine switch off.
    2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and the No. 3 indoor electrical key oscillator (inside luggage).

      OK

      Connectors are properly connected.

    NG → CONNECT CONNECTORS PROPERLY 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR) 
    1. Disconnect the D40 and D48 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the H9 No. 3 indoor electrical key oscillator (inside luggage) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D40-9 (CLG7) - H9-1 (ANTE7) Always Below 1 Ω
      D40-8 (CG7B) - H9-3 (CLGB) Always Below 1 Ω
      D48-11 (GND) - Body ground Always Below 1 Ω
      D40-9 (CLG7) or H9-1 (ANTE7) - Body ground Always 10 kΩ or higher
      D40-8 (CG7B) or H9-3 (CLGB) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR) 
    Fig 1: Inspecting Certification ECU (Smart Key ECU Assembly) (Output To No. 3 Indoor Electrical Key Oscillator) With Waveform
    GTY392851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TEXT IN ILLUSTRATION

    *a Component with harness connected
    (Certification ECU (smart key ECU assembly))    		 *b Waveform
    *c Within approximately 30 seconds from when the door is closed *d After approximately 30 seconds from when the door is closed
    1. Reconnect the D40 and D48 certification ECU (smart key ECU assembly) connector.
    2. Reconnect the H9 No. 3 indoor electrical key oscillator (inside luggage) connector.
    3. Using an oscilloscope, check the waveform.

      HINT: 

      Check that the customizing "Ignition Available Area" setting of smart key system is All. Refer to CUSTOMIZE PARAMETERS [05/2013 - ] .

      OK

      Tester Connection Switch Condition Tool Setting Specified Condition
      D40-9 (CLG7) - D48-11 (GND) Procedure:
      1. Engine switch off
      2. Door is open
      3. Door is closed
      4. 30 seconds elapse
      5. Electrical key transmitter not inside vehicle
      		 2 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform)
      D40-8 (CG7B) - D48-11 (GND) Procedure:
      1. Engine switch off
      2. Door is open
      3. Door is closed
      4. 30 seconds elapse
      5. Electrical key transmitter not inside vehicle
      		 2 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform)

    NG → See step   6 

    OK: Go to next step 

  4. REPLACE NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR (INSIDE LUGGAGE) 
    1. Temporarily replace the No. 3 indoor electrical key oscillator (inside luggage) with a new or normally functioning one. Refer to REMOVAL [05/2013 - ] .

    NEXT: Go to next step 

  5. CHECK DTC OUTPUT 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR [05/2013 - ] .
    2. Recheck for DTCs. Refer to DTC CHECK / CLEAR [05/2013 - ] .

      OK

      B27A7 is not output.

    NG → See step   6 

    OK → END (NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR WAS DEFECTIVE) 

  6. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [05/2013 - ] 
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