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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT FUSE (RR-IG1-2) 
    1. Remove the RR-IG1-2 fuse from the luggage room junction block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTOR SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      RR-IG1-2 fuse Always Below 1 Ω

    NG: REPLACE FUSE 

    OK: Go to Next Step 

  2. CHECK REAR JUNCTION BLOCK ECU (SMOK VOLTAGE) 
    1. Remove the rear junction block ECU with its connectors still connected.
    2. Measure the voltage according to the value(s) in the table below when applying or not applying cigarette smoke

      Standard voltage 

      TESTER CONNECTOR SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      S62-7 (SMOK) - Body ground Power switch ON (IG) Rear cooler AUTO switch ON
      Apply cigarette smoke      		 4.0 V or higher
      Power switch ON (IG) Rear cooler AUTO switch ON
      No cigarette smoke      		 Below 1 V
      Fig 1: Identifying Terminals Of S62 Rear Junction Block ECU Connector
      G05774391Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 3 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

  3. INSPECT SMOKE SENSOR 
    1. Remove the smoke sensor (see REMOVAL  ).
    2. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 3.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTOR SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2 - 3 There is no cigarette smoke Below 1.0 V
      There is cigarette smoke 4.0 V or higher
      NOTE: Since the sensor determines the amount of smoke based on the changes in the amount of light, check the sensor in an area with as little ambient light as possible.
      Fig 2: Inspecting Smoke Sensor
      G05774392Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SMOKE SENSOR  (See REMOVAL  )

    OK: Go to Next Step 

  4. CHECK HARNESS AND CONNECTOR (REAR JUNCTION BLOCK ECU - REAR AIR CONDITIONING HARNESS) 
    1. Disconnect the S62 rear junction block ECU connector.
    2. Disconnect the S28 rear air conditioning harness connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTOR SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      S62-7 (SMOK) - S28-13 (S) Always Below 1 Ω
      S62-7 (SMOK) - Body ground Always 10 kΩ or higher
      Fig 3: Identifying Terminals Of S62 Rear Junction Block ECU Connector
      G05774393Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  5. REPLACE REAR AIR CONDITIONING HARNESS 
    1. Replace the rear air conditioning harness with a normal one and check that the condition returns to normal (see REMOVAL  ).

      OK: Same problem does not occur. 

    NG: REPLACE REAR JUNCTION BLOCK ECU 

    OK: END (REAR AIR CONDITIONING HARNESS IS DEFECTIVE) 

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