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Generator Signal Circuit: 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. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Body No. 5 / Data List.
    5. Read the display on the Techstream.
      BODY NO. 5 (FRONT CONTROLLER)

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Alt L Signal Alternator L terminal signal / ON or OFF ON: Engine start
      OFF: Except engine start
      -

      OK

      Normal conditions listed above are displayed.

    NG → See step   2 

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

  2. INSPECT GENERATOR ASSEMBLY 
    1. Inspect generator assembly. Refer to INSPECTION .

      OK

      Generator assembly is normal.

    NG → CHECK AND REPLACE GENERATOR ASSEMBLY 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (GENERATOR - FRONT CONTROLLER) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 1: Identifying 1H Generator (Front Controller) Connector Terminals
      GTY177932Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage

      Tester Connection Condition Specified Condition
      1H-6 - Body ground Engine running 10 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

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