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DTC B2784: Antenna Coil Open / Short: Procedure

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. RECONFIRM DTC 
    1. Clear the DTC and repeat the procedure to re-check it. Refer to DTC CHECK / CLEAR .

      OK

      DTC is not output.

    OK → END (SYSTEM IS NORMAL) 

    NG: Go to next step 

  2. CHECK WIRE HARNESS (CERTIFICATION ECU - ENGINE SWITCH) 
    1. Disconnect the D39 ECU connector.
      Fig 1: Identifying D39 Certification ECU Connector Terminals
      GTY206679Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the D21 switch connector.
      Fig 2: Identifying D21 Engine Switch Connector Terminals
      GTY179966Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Resistance

      Tester Connection Condition Specified Condition
      D39-8 (TXCT) - D21-9 (TXCT) Always Below 1 Ω
      D39-9 (CODE) - D21-10 (CODE) Always Below 1 Ω
      D39-30 (VC5) - D21-14 (VC5) Always Below 1 Ω
      D39-40 (AGND) - D21-8 (AGND) Always Below 1 Ω
      D39-8 (TXCT) - Body ground Always 10 kΩ or higher
      D39-9 (CODE) - Body ground Always 10 kΩ or higher
      D39-30 (VC5) - Body ground Always 10 kΩ or higher
      D39-40 (AGND) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. REPLACE ENGINE SWITCH (CHECK OPERATION OF ENGINE SWITCH) 
    1. Replace the engine switch.
    2. Clear the DTC and repeat the procedure to re-check it. Refer to DTC CHECK / CLEAR .

      OK

      DTC is not output.

    OK → END (ENGINE SWITCH IS DEFECTIVE) 

    NG → REPLACE CERTIFICATION ECU