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Terminals Of Ecu

  1. CHECK ECM 
    Fig 1: Identifying ECM Connector Terminals
    G05820448Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the voltage and resistance of each terminal of the connectors.
      ECU TERMINAL REFERENCE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +BM (E83-20) - E1 (E83-104) P - BR Power supply Always 10 to 14 V
      BATT (A53-20) - E1 (E83-104) L - BR Power supply Always 10 to 14 V
      +B1 (A53-1) - E1 (E83-104) B-R - BR Power supply Power switch ON (IG) 10 to 14 V
      +B (A53-2) - E1 (E83-104) B-R - BR Power supply Power switch ON (IG) 10 to 14 V
      IGSW (A53-11) - E1 (E83-104) B-W - BR Ignition power supply Power switch ON (IG) Below 1 V
      IGSW (A53-11) - E1 (E83-104) B-W - BR Ignition power supply Power switch OFF 10 to 14 V
      RDEF (A53-14) - E1 (E83-104) G-B - BR DEFOG relay Power switch ON (IG) Rear defogger switch ON Below 1 V
      RDEF (A53-14) - E1 (E83-104) G-B - BR DEFOG relay Power switch ON (IG) Rear defogger switch OFF 10 to 14 V
      ME01 (E83-43) - Body ground B - Body ground Ground Always Below 1 Ω
      E1 (E83-104) - Body ground BR - Body ground Ground Always Below 1 Ω
      E02 (E83-106) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E01 (E83-105) - Body ground W-B - Body ground Ground Always Below 1 Ω
      EC (A53-32) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, the ECM may have a malfunction.

  2. CHECK AIR CONDITIONING AMPLIFIER (A/C ECU) 
    Fig 2: Identifying Air Conditioning Amplifier (A/C ECU) Connector Terminals
    G05300249Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the K52 amplifier connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      ECU TERMINAL REFERENCE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG+ (K52-21) - GND (K52-20) W - W-B Ignition power supply Power switch ON (IG) 10 to 14 V
      IG+ (K52-21) - GND(K52-20) W - W-B Ignition power supply Power switch OFF Below 1 V
      B (K52-1) - GND (K52-20) L - W-B Battery power supply Always 10 to 14 V
      GND (K52-20) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction on the wire harness side.

  3. CHECK MULTI-DISPLAY 
    Fig 3: Identifying Multi-Display Connector Terminals
    G05300250Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the K46 multi-display connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      ECU TERMINAL REFERENCE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (K46-3) - GND1 (K46-10) B - W-B Ignition power supply Power switch ON (IG) 10 to 14 V
      IG (K46-3) - GND1 (K46-10) B - W-B Ignition power supply Power switch OFF Below 1 V
      +B1 (K46-1) - GND1 (K46-10) O - W-B Battery power supply Always 10 to 14 V
      GND1 (K46-10) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction on the wire harness side.

  4. CHECK POWER SOURCE CONTROL ECU 
    Fig 4: Identifying Power Source Control ECU Connector Terminals
    G05300251Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the K73 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      ECU TERMINAL REFERENCE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      AM1 (K73-33) - Body ground O - Body ground +B power supply Always 10 to 14 V
      GND2 (K73-6) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction on the wire harness side.

    3. Reconnect the K73 ECU connector.
    4. Measure the voltage of the connector.
      ECU TERMINAL REFERENCE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG1D (K73-34) - GND2 (K73-6) P - W-B IG1 control signal Power switch ON (ACC) Below 1 V
      IG1D (K73-34) - GND2 (K73-6) P - W-B IG1 control signal Power switch OFF 10 to 14 V

      If the result is not as specified, the ECU may have a malfunction.

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