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Terminals Of Ecu

WARNING: This page is about a different car, the 2005 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT INSTRUMENT PANEL J/B ASSY (MULTIPLEX NETWORK BODY ECU) 
    Fig 1: Identifying Terminals Of ECU
    G02607853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the B7 ECU, 1C, 1E, 1K and 1L and 1C J/B connectors.
    2. Check the voltage and resistance between each terminal of the wire harness side connectors and body ground.

    Standard: 

    WIRING COLOR

    Symbols (Terminal No.) Wiring Color Condition Specified Condition
    BECU (1C-24) - Body ground W-L - Body ground Constant 10 to 14 V
    BECU (1L-7) - Body ground W-L - Body ground
    MPX1 (1E-7) - Body ground R-L - Body ground Constant 10 kΩ or higher
    MPX2 (B7-21) - Body ground R-L - Body ground Constant 10 kΩ or higher
    GND1 (1L-16) - Body ground W-B - Body ground Constant Below 1 Ω
    GND2 (1K-17) - Body ground W-B - Body ground Constant Below 1 Ω

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

  2. CHECK AIRBAG SENSOR ASSY (AIRBAG ECU) 
    Fig 2: Identifying Airbag Sensor Assy (Airbag ECU)
    G02607854Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A21 ECU connector.
    2. Check the voltage and resistance of each terminal of the wire harness side.

    Standard: 

    Fig 3: ECU Specified Condition Table (1 Of 4)
    G02607855Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  3. CHECK ECM 
    Fig 4: Checking ECM
    G02607856Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E4, E5 and E6 ECM connectors.
    2. Check the voltage and resistance of each terminal of the wire harness side connector.

    Standard: 

    Fig 5: ECU Specified Condition Table (2 Of 4)
    G02607857Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  4. CHECK A/C AMPLIFIER ASSY (A/C ECU) 
    Fig 6: Checking A/C Amplifier Assy (A/C ECU)
    G02607858Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A9 ECU connector.
    2. Check the voltage and resistance of each terminal of the wire harness side connector.

    Standard: 

    Fig 7: ECU Specified Condition Table (3 Of 4)
    G02607859Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  5. CHECK COMBINATION METER 
    Fig 8: Checking Combination Meter
    G02607860Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C10 meter connector.
    2. Check the voltage and resistance of each terminal of the wire harness side connector.

    Standard: 

    Fig 9: ECU Specified Condition Table (4 Of 4)
    G02607861Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  6. CHECK MULTIPLEX NETWORK DOOR ECU REAR RH (POWER SLIDE DOOR ECU RH) 
    Fig 10: Checking Multiplex Network Door ECU Rear RH (Power Slide Door ECU RH)
    G02607862Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P27 and P28 ECU connectors.
    2. Check the voltage and resistance of each terminal of the wire harness side connectors.

    Standard: 

    WIRING COLOR

    Symbols (Terminal No.) Wiring Color Condition Specified Condition
    B (P28-2) - GND (P28-8) B - W-B Constant 10 to 14 V
    ECUB (P27-10) - GND (P28-8) W - W-B Constant 10 to 14 V
    MPX1 (P27-22) - Body ground R - Body ground Constant 10 kΩ or higher
    GND (P28-8) - Body ground W-B - Body ground Constant Below 1 Ω

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

  7. CHECK MULTIPLEX NETWORK DOOR ECU REAR LH (POWER SLIDE DOOR ECU LH) 
    Fig 11: Checking Multiplex Network Door ECU Rear LH (Power Slide Door ECU LH)
    G02607863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P25 and P26 ECU connectors.
    2. Check the voltage and resistance of each terminal of the wire harness side connectors.

    Standard: 

    WIRING COLOR

    Symbols (Terminal No.) Wiring Color Condition Specified Condition
    B (P26-2) - GND (P26-8) B-W - W-B Constant 10 to 14 V
    ECUB (P25-10) - GND (P26-8) W - W-B Constant 10 to 14 V
    WIRING COLOR

    Symbols (Terminal No.) Wiring Color Condition Specified Condition
    MPX1 (P25-22) - Body ground R - Body ground Constant 10 kΩ or higher
    GND (P26-8) - Body ground W-B - Body ground Constant Below 1 Ω

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

  8. CHECK MULTIPLEX NETWORK DOOR ECU BACK (POWER BACK DOOR ECU) 
    Fig 12: Checking Multiplex Network Door ECU Back (Power Back Door ECU)
    G02607864Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P13 and P14 ECU connectors.
    2. Check the voltage and resistance of each terminal of the wire harness side connectors.

    Standard: 

    Fig 13: ECU Specified Condition Table
    G02607865Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

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