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Transmission Control Switch Circuit: Wiring Diagram

Fig 1: Wiring Diagram - Transmission Control Switch Circuit
G04052946Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. CHECK HARNESS AND CONNECTOR (BATTERY - TRANSMISSION CONTROL SWITCH) 
    1. Disconnect the transmission control switch connector of shift lock control unit assembly.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Switch Condition Tester Connection Specified Condition
      Engine switch on (IG) 3 - Body ground 10 to 14 V
      Engine switch off   Below 1 V
      Fig 2: Identifying Transmission Control Switch Connector Terminals
      G04052947Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK : GO TO NEXT STEP 

  2. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      5 - Body ground Below 1 Ω
      Fig 3: Checking Transmission Control Switch - Body Ground
      G04052948Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK : GO TO NEXT STEP 

  3. INSPECT TRANSMISSION CONTROL SWITCH 
    1. Measure resistance between each terminal of shift lock control unit assembly when the shift lever is moved to each position.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Shift Position Tester Connection Specified Condition
      S, "+" and "-" 3 - 7 Below 1 Ω
      Except S, "+" and "-"   10 kΩ or higher
      Press continuously "+" (Up shift) 2 - 5 Below 1 Ω
      S   10 kΩ or higher
      Press continuously "-" (Down shift) 1 - 5 Below 1 Ω
      S   10 kΩ or higher
      Fig 4: Inspecting Transmission Control Switch
      G04052949Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPLACE TRANSMISSION CONTROL SWITCH 

    OK : GO TO NEXT STEP 

  4. CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM) 
    1. Connect the transmission control switch connector of shift lock control unit assembly.
    2. Disconnect the ECM connector.
    3. Turn the ignition switch on (IG) position, and measure the voltage according to the value(s) in the table below when the shift lever is moved to each position.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Shift Position Tester Connection Specified Condition
      S, "+" and "-" A6-9 (S) - Body ground 10 to 14 V
      Except S, "+" and "-"   Below 1 V
      Fig 5: Identifying ECM A6 Connector
      G04052950Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Turn the ignition switch off position.
    5. Disconnect the ECM connector.
    6. Measure the resistance according to the value(s) in the table below when the shift lever is moved to each position.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Shift Position Tester Connection Specified Condition
      Press continuously "+" (Up shift) A6-30 (SFTU) - Body ground Below 1 Ω
      S   10 kΩ or higher
      Press continuously "-" (Down shift) A6-19 (SFTD) - Body ground Below 1 Ω
      S   10 kΩ or higher
      Fig 6: Identifying ECM A6 Connector
      G04052951Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

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