Security Indicator Light Circuit (From 8/2009): Procedure

2010 Lexus RX 450h 3.5 BSECTION Procedure
  1. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Access / Active Test.
    5. Perform the Active Test according to the display on the Techstream.
      SMART ACCESS (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

      Tester Display Test Part Control Range Diagnostic Note
      Immobilizer Indicator Security indicator light ON or OFF -

      OK

      The security indicator light turns on and off according to operation via the Techstream.

    NG → See step   2 

    OK → See step   4 

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - RADIO RECEIVER ASSEMBLY) 
    1. Disconnect the certification ECU (smart key ECU assembly) connector.
    2. Disconnect the radio receiver assembly connector.
      Fig 1: Identifying Radio Receiver Assembly Connector
      GTY280901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F58-2 (IND) - G8-7 (LP) Always Below 1 Ω
      F58-2 (IND) - Body ground Always 10 kΩ or higher
      G8-7 (LP) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Certification ECU (Smart Key ECU Assembly))
      *2 Front view of wire harness connector
      (to Radio Receiver Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL 
  4. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL 
  5. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 2: Measure The Resistance
      GTY278851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      G8-9 (GND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Radio Receiver Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   3 

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
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