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July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

HINT

Start the engine before inspection. Check the IG1 relay or battery if the engine does not start.

  1. INSPECT FUSE (ECU-IG LH) 
    1. Remove the ECU-IG LH fuse from the cowl side junction block LH
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATIONS

      Tester Item Condition Specified Condition
      ECU-IG LH fuse Always Below 1 Ω
      Fig 1: Identifying ECU-IG LH Fuse
      G05755300Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUSE (ECU-IG LH) 

    OK: Go to next step 

  2. INSPECT A/C AMPLIFIER (IG+ - GND) 
    1. Remove the A/C amplifier with its connectors still connected.
    2. Turn the engine switch on (IG)
    3. Measure the voltage according to the value(s) in the table below

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATIONS

      Tester Connection Switch Condition Specified Condition
      J58-21 (IG+) - J58-20 (GND) Engine switch on (IG) 11 to 14 V
    4. Fig 2: Identifying J58 Connector Terminals
      G05755301Courtesy 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. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY) 
    1. Disconnect the A/C amplifier connector
    2. Measure the voltage according to the value(s) in the table below

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATIONS

      Tester Connection Switch Condition Specified Condition
      J58-21 (IG+) - Body ground Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
    3. Fig 3: Identifying J58 Connector Terminals (IG+)
      G05755302Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATIONS

      Tester Connection Condition Specified Condition
      J58-20 (GND) - Body ground Always Below 1 Ω
    2. Fig 4: Identifying J58 Connector Terminals (GND)
      G05755289Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE A/C AMPLIFIER  (See REMOVAL  )