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Terminals Of Ecu

WARNING: This page is about a different car, the 2008 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT GATEWAY ECU 
    Fig 1: Identifying Gateway ECU G3 Connector Terminals
    G05274947Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the G3 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (63-1) - Body ground G - Body ground Main power supply (IG) Turn the ignition switch to the ON position 10 to 14 V
      IG (G3-1) - Body ground G - Body ground Main power supply (IG) Ignition switch off Below 1 V
      ACC (G3-2) - Body ground L - Body ground Main power supply (ACC) Turn the ignition switch to the ACC position 10 to 14 V
      ACC (G3-2) - Body ground L - Body ground Main power supply (ACC) Ignition switch off Below 1 V
      BATT (G3-10) - Body ground Y - Body ground Main power supply (+B) Always 10 to 14 V
      GND (G3-24) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPD1 (G3-3) - Body ground O - Body ground Multiplex communication line Always 10 kΩ or higher
      MPD2 (G3-12) - Body ground BR - Body ground (*1)
      R - Body ground (*2)      		 Multiplex communication line Always 10 kΩ or higher
      MPI1 (G3-4) - Body ground W - Body ground Multiplex communication line Always 10 kΩ or higher
      MPI2 (G3-13) - Body ground V - Body ground Multiplex communication line Always 10 kΩ or higher
      HINT:
      *1: with Air Suspension System
      *2: without Air Suspension System

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

  2. INSPECT MAIN BODY ECU 
    Fig 2: Identifying B5, 1E, 1A, 1D, 1F & 1M Connector Terminals
    G05274948Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the B5, 1E, 1 A, 1D, 1F and 1M connectors.
    2. Measure the voltage and resistance between each terminal of the wire harness side connectors.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      BATB (1A-1) - Body ground W - Body ground (*1)
      W - Body ground (*2)      		 Main power supply (+B) Always 10 to 14 V
      ALTB (1D-16) - Body ground W - Body ground Main power supply (+B) Always 10 to 14 V
      BECU (1D-10) - Body ground L-B Body ground Main power supply (+B) Always 10 to 14 V
      GND2 (1M-9) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      GND1 (1F-10) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (1E-7) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX2 (B5-21) - Body ground 0 - Body ground Multiplex communication line Always 10 kΩ or higher
      HINT:
      *1: with Air Suspension System
      *2: without Air Suspension System If the result is not as specified, there may be a malfunction on the wire harness side.
  3. INSPECT AFS ECU 
    Fig 3: Identifying A14 Connector Terminals
    G05274949Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A14 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (A14-2) - Body ground P - Body ground Main power supply (IG) Turn the ignition switch to the ON position 10 to 14 V
      IG (A14-2) - Body ground P - Body ground Main power supply (IG) Ignition switch off Below 1V
      IGS (A14-12) - Body ground O - Body ground Main power supply (IG) Turn the ignition switch to the ON position 10 to 14 V
      IGS (A14-12) - Body ground O - Body ground Main power supply (IG) Ignition switch off Below 1 V
      E1 (A14-1) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      E1S (A14-11) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (A14-5) - Body ground W - Body ground Multiplex communication line Always 10 kΩ or higher

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

  4. INSPECT POWER WINDOW MASTER SWITCH 
    Fig 4: Identifying P22 ECU Connector Terminals
    G05274950Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P22 ECU connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (P22-9) - Body ground L-B - Body ground Main power supply (+B) Always 10 to 14 V
      GND (P22-2) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (P22-7) - Body ground R - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX2 (P22-8) - Body ground GR - Body ground Multiplex communication line Always 10 kΩ or higher

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

  5. INSPECT REMOTE CONTROL MIRROR ECU RH 
    Fig 5: Identifying R27 Connector Terminals
    G05274951Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the R27 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (R27-7) - Body ground L-B - Body ground Main power supply (+B) Always 10 to 14 V
      GND (R27-1) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (P27-6) - Body ground L - Body ground Multiplex communication line Always 10 kΩ or higher

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

  6. INSPECT REMOTE CONTROL MIRROR LH 
    Fig 6: Identifying R26 Connector Terminals
    G05274952Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the R26 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (R26-7) - Body ground L-B - Body ground Main power supply (+B) Always 10 to 14 V
      GND (R26-1) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (P26-6) - Body ground R - Body ground Multiplex communication line Always 10 kΩ or higher

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

  7. INSPECT TILT AND TELESCOPIC ECU 
    Fig 7: Identifying T4 Connector Terminals
    G05274953Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T4 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (T4-2) - Body ground Y - Body ground Main power supply (+B) Always 10 to 14 V
      ECUB (T4-9) - Body ground SB - Body ground Main power supply (+B) Always 10 to 14 V
      GND (T4-11) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (T4-5) - Body ground GR - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX2 (T4-14) - Body ground O - Body ground Multiplex communication line Always 10 kΩ or higher

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

  8. INSPECT AUTO WIPER ECU 
    Fig 8: Identifying A28 Connector Terminals
    G05274954Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A28 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (A28-8) - Body ground GR - Body ground Main power supply (+B) Always 10 to 14 V
      E (A28-12) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (A28-1) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher

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

  9. INSPECT TIRE PRESSURE WARNING ECU 
    Fig 9: Identifying T23 Connector Terminals
    G05274955Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T23 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (T23-1) - Body ground Y - Body ground Main power supply (IG) Turn the ignition switch to the ON position 10 to 14 V
      IG (T23-1) - Body ground Y - Body ground Main power supply (IG) Ignition switch off Below 1 V
      GND (T23-7) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (T23-6) - Body ground R - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX2 (T23-12) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher

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

  10. INSPECT A/C AMPLIFIER 
    Fig 10: Identifying A8 Connector Terminals
    G05274956Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A8 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (A8-2) - Body ground SB - Body ground Main power supply (+B) Always 10 to 14 V
      GND (A8-6) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX+ (A8-3) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX- (A8-4) - Body ground W - Body ground Multiplex communication line Always 10 kΩ or higher

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

  11. INSPECT COMBINATION METER ECU 
    Fig 11: Identifying C8 & C9 Connector Terminals
    G05274957Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C8 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      C8-15 - Body ground SB - Body ground Main power supply (+B) Always 10 to 14 V
      C8-16 - Body ground O - Body ground Main power supply (+B) Always 10 to 14 V
      C8-1 - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      C9-1 - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      C8-5 - Body ground Y - Body ground Multiplex communication line Always 10 kΩ or higher
      C9-4 - Body ground Y - Body ground Multiplex communication line Always 10 kΩ or higher

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

  12. INSPECT POWER SEAT ECU 
    Fig 12: Identifying P32 & P33 Connector Terminals
    G05274958Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P32 and P33 connectors.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SYSB (P32-8) - Body ground GR - Body ground Main power supply (+B) Always 10 to 14 V
      +B (P33-5) - Body ground LG - Body ground Main power supply (+B) Always 10 to 14 V
      GND (P33-1) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (P32-1) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher

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

  13. INSPECT SLIDING ROOF CONTROL ECU (MULTI-PANEL MOON ROOF TYPE) 
      Fig 13: Identifying M12 Connector Terminals (1 Of 2)
      G05274959Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the M12 connector.
    2. Check the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      B (M12-4) - Body ground P - Body ground Main power supply (+B) Always 10 to 14 V
      ECUB (M12-10) - Body ground SB - Body ground Main power supply (+B) Always 10 to 14 V
      E (M12-8) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (M12-5) - Body ground R - Body ground Multiplex communication line Always 10 kΩ or higher

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

  14. INSPECT SLIDING ROOF CONTROL ECU (STANDARD MOON ROOF TYPE) 
      Fig 14: Identifying M12 Connector Terminals (2 Of 2)
      G05274960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the M12 connector.
    2. Check the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      B (M12-1) - Body ground P - Body ground Main power supply (+B) Always 10 to 14 V
      ECUB (M12-5) - Body ground SB - Body ground Main power supply (+B) Always 10 to 14 V
      E (M12-7) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (M12-10) - Body ground R - Body ground Multiplex communication line Always 10 kΩ or higher

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

  15. INSPECT CENTER CLUSTER INTEGRATION PANEL 
    Fig 15: Identifying C4 Connector Terminals
    G05274961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C4 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (C4-1) - Body ground O - Body ground Main power supply (+B) Always 10 to 14 V
      GND (C4-7) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX+ (C4-5) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX- (C4-12) - Body ground GR - Body ground Multiplex communication line Always 10 kΩ or higher

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

  16. INSPECT RAIN SENSOR 
    Fig 16: Identifying R7 Connector Terminals
    G05274962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the R7 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SIG (R7-1) - Body ground P - Body ground Main power supply (IG) Turn the ignition switch to the ON position 10 to 14 V
      SIG (R7-1) - Body ground P - Body ground Main power supply (IG) Ignition switch off Below 1 V
      ES (R7-3) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX (R7-2) - Body ground V - Body ground Multiplex communication line Always 10 kΩ or higher

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

  17. INSPECT AIRBAG SENSOR ASSEMBLY 
    Fig 17: Identifying A20 Connector Terminals
    G05274963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A20 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG2 (A20-5) - Body ground B - Body ground Main power supply (IG) Turn the ignition switch to the ON position 10 to 14 V
      IG2 (A20-5) - Body ground B - Body ground Main power supply (IG) Ignition switch off Below 1 V
      E1 (A20-27) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      E2 (A20-28) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (A20-24) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX2 (A20-22) - Body ground BR - Body ground Multiplex communication line Always 10 kΩ or higher

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

  18. INSPECT POWER BACK DOOR ECU 
    Fig 18: Identifying P13 & P14 Connector Terminals
    G05274964Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P13 and P14 connectors.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ECUB (P13-10) - Body ground BR - Body ground Main power supply (+B) Always 10 to 14 V
      B (P14-2) - Body ground Y - Body ground Main power supply (+B) Always 10 to 14 V
      GND (P14-8) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (P13-22) - Body ground SB - Body ground Multiplex communication line Always 10 kΩ or higher

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

  19. INSPECT TRANSPONDER KEY ECU 
    Fig 19: Identifying T9 Connector Terminals
    G05274965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T9 connector.
    2. Measure the voltage and resistance of each terminal of the wire harness side connector.

      Standard 

      VOLTAGE AND RESISTANCE SPECIFICATION TABLE

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (T9-1) - Body ground SB - Body ground Main power supply (+B) Always 10 to 14 V
      GND (T9-14) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      MPX1 (T9-4) - Body ground O - Body ground Multiplex communication line Always 10 kΩ or higher
      MPX2 (T9-5) - Body ground O - Body ground Multiplex communication line Always 10 kΩ or higher

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

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