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Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus ES 350. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT FUSE (ECU-IG NO. 2 OR H-LP LVL) 
    1. Remove the ECU-IG No. 2 fuse or H-LP LVL fuse from the instrument panel junction block assembly.
    2. Measure the resistance of the fuse.

      Standard resistance: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step. 

  2. INSPECT AFS ECU 
    1. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A22-14 (IGS) - A22-22 (E1) Engine switch off Below 1 V
      A22-14 (IGS) - A22-22 (E1) Engine switch on (IG) 10 to 14 V
      A22-15 (IG) - A22-22 (E1) Engine switch off Below 1 V
      A22-15 (IG) - A22-22 (E1) Engine switch on (IG) 10 to 14 V
      Fig 1: Identifying A22 Connector Terminals
      G05252364Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    NG: Go to next step. 

  3. CHECK WIRE HARNESS (AFS ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the A22 AFS ECU connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A22-14 (IGS) - Body ground Engine switch on (IG) 10 to 14 V
      A22-15 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 2: Disconnecting A22 AFS ECU Connector
      G05252365Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A22-22 (E1) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE AFS ECU