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Terminals Of Ecu: Notes

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK MULTIPLEX NETWORK GATEWAY ECU 
    1. Disconnect the G3 ECU connector.
      Fig 1: Identifying G3 ECU Connector
      G04116758Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      BATT (G3-10) - GND (G3 24) SB - W-B +B (BATT) power supply Always 10 to 14 V
      IG (G3-1) - Body ground Y - Body ground Ignition power supply Ignition switch ON 10 to 14 V
      ACC (G3-2) - Body ground L - Body ground ACC power supply Ignition switch ON 10 to 14 V
      SIL (G3-7) - Body ground GR - Body ground Bus "+" line During transmission Pulse generation
      MP11 (G3-4) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      MP12 (G3-13) - Body ground O - Body ground MPX line Always 10 kΩ or higher
      MPD1 (G3-3) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      MPD2 (G3-12) - Body ground R - Body ground W-B - Body ground Always 10 kΩ or higher
      GND (G3-24) - Body ground W-B - Body ground Ground Always Below 1 Ω
      GTX-(G3-21) - Body ground B - Body ground AVC-LAN line Always 10 kΩ or higher
      GTX+ (G3-6) - Body ground R - Body ground AVC-LAN line Always 10 kΩ or higher

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

  2. CHECK INSTRUMENT PANEL JUNCTION BLOCK (MULTIPLEX NETWORK BODY ECU) 
    1. Disconnect the 1E, 1D and 1F junction block connectors.
    2. Disconnect the B5 ECU connector.
      Fig 2: Identifying Instrument Panel Junction Block (Multiplex Network Body ECU)
      G04116759Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance and voltage of the wire harness side connectors.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      BECU (1F-10) - Body ground W - Body ground +B (BECU) power supply Always 10 to 14 V
      MPX1 (1E-7) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      MPX2 (B5-21) - Body ground O - Body ground MPX line Always 10 kΩ or higher
      GND1 (1F-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.

  3. CHECK CENTER CLUSTER INTEGRATION PANEL (W/O LEXUS NAVIGATION SYSTEM) 
    1. Disconnect the C4 panel connector.
      Fig 3: Identifying C4 Panel Connector
      G04116760Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG+ (C4-9) - Body ground LG - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      MPX+ (C4-5) - Body ground L - Body ground MPX line Always 10 kΩ or higher
      MPX-(C4-12) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      GND (C4-7) - 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 AUTO WIPER ECU 
    1. Disconnect the A28 and A29 ECU connectors.
      Fig 4: Identifying A28 And A29 ECU Connectors
      G04116761Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      WIG (A29-10) - Body ground Y - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      MPX1 (A28-1) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      E (A28-12) - 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.

  5. CHECK AFS ECU (W/ ADAPTIVE FRONT-LIGHT SYSTEM) 
    1. Disconnect the A14 ECU connector.
      Fig 5: Identifying A15 And A14 ECU Connector
      G04116762Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and the resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (A14-2) - Body ground P - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      IGS (A14-12) - Body ground P - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      MPX1 (A14-5) - Body ground P - Body ground MPX line Always 10 kΩ or higher
      E1 (A14-1) - 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.

  6. CHECK POSITION CONTROL ECU AND SWITCH ASSEMBLY (W/ DRIVING POSITION MEMORY) 
    1. Disconnect the P32 and P33 ECU connectors.
      Fig 6: Identifying P32 And P33 ECU Connectors
      G04116763Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and the resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (P33-5) - Body ground LG - Body ground +B (+B) power supply Always 10 to 14 V
      MPX1 (P32-1) - Body ground W - Body ground MPX line Always 10 kΩ or higher
      GND (P33-1) - 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.

  7. CHECK AIR CONDITIONING AMPLIFIER (A/C ECU) 
    1. Disconnect the A8 amplifier connector.
      Fig 7: Identifying A7 And A8 Amplifier Connector
      G04116764Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG+ (A8-1) - Body ground Y - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      MPX+ (A8-3) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      MPX- (A8-4) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      GND (A8-6) - 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.

  8. CHECK CENTER AIRBAG SENSOR ASSEMBLY 
    1. Disconnect the A20 sensor connector.
      Fig 8: Identifying A21, A22 And A20 Sensor Connector
      G04116765Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG2 (A20-5) - Body ground B - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      MPX1 (A20-24) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      MPX2 (A20-22) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      E2 (A20-28) - 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.

  9. CHECK COMBINATION METER ASSEMBLY (METER ECU) 
    1. Disconnect the C8 and C9 meter connectors.
      Fig 9: Identifying C8 And C9 Meter Connectors
      G04116766Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      B (C8-15) - Body ground SB - Body ground +B (B) power supply Always 10 to 14 V
      B (C8-16) - Body ground O - Body ground +B (B) power supply Always 10 to 14 V
      MPX+ (C9-4) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      MPX- (C8-5) - Body ground Y - Body ground MPX line Always 10 kΩ or higher
      E (C9-1) - 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.

  10. CHECK SLIDING ROOF DRIVE GEAR (SLIDING ROOF CONTROL ECU) 
    1. Disconnect the M12 driver gear connector.
      Fig 10: Identifying M12 Driver Gear Connector
      G04116767Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and the resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      B (M12-1) - Body ground P - Body ground +B (B) power supply Always 10 to 14 V
      MPX1 (M12-10) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      E (M12-7) - 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.

  11. CHECK MULTIPLEX TILT AND TELESCOPIC ECU (W/DRIVING POSITION MEMORY) 
    1. Disconnect the T4 ECU connector.
      Fig 11: Identifying T4 ECU Connector
      G04116768Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      +B (T4-2) - Body ground Y - Body ground +B (+B) power supply Always 10 to 14 V
      MPX1 (T4-5) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      MPX2 (T4-14) - Body ground O - Body ground MPX line Always 10 kΩ or higher
      GND (T4-11) - 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.

  12. CHECK RAIN SENSOR 
    1. Disconnect the R7 sensor connector.
      Fig 12: Identifying R7 Sensor Connector
      G04116769Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      SIG (R7-1) - Body ground P - Body ground Ignition switch (on) signal Ignition switch ON 10 to 14 V
      MPX (R7-2) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      ES (R7-3) - 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.

  13. CHECK MULTIPLEX NETWORK MASTER SWITCH 
    1. Disconnect the P22 switch connector.
      Fig 13: Identifying P22 Switch Connector
      G04116770Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

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

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

  14. CHECK MULTIPLEX BACK DOOR ECU 
    1. Disconnect the P13 and P14 ECU connectors.
      Fig 14: Identifying P13 And P14 ECU Connectors
      G04116771Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      B (P14-2) - Body ground Y - Body ground +B (B) power supply Always 10 to 14 V
      MPX1 (P13-22) - Body ground W - Body ground MPX line Always 10 kΩ or higher
      GND (P14-8) - 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.

  15. CHECK TRANSPONDER KEY ECU 
    1. Disconnect the T9 ECU connector.
      Fig 15: Identifying T9 ECU Connector
      G04116772Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance and voltage of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (T9-1) - Body ground V - Body ground B (CPUB) power supply Always 10 to 14 V
      MPX1 (T9-4) - Body ground O - Body ground MPX line Always 10 kΩ or higher
      MPX2 (T9-5) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      GND (T9-14) - 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.

  16. CHECK OUTER MIRROR CONTROL ECU LH 
    1. Disconnect the R21 ECU connector.
      Fig 16: Identifying R23 And R21 ECU Connector
      G04116773Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance and voltage of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (R27-7) - Body ground L-B - Body ground B (CPUB) power supply Always 10 to 14 V
      MPX1 (R27-6) - GND (R27-1) R - W-B MPX line Always 10 kΩ or higher
      GND (R27-1) - 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.

  17. CHECK OUTER MIRROR CONTROL ECU RH 
    1. Disconnect the R22 ECU connector.
      Fig 17: Identifying R22 And R28 ECU Connector
      G04116774Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance and voltage of the wire harness side connector.
      TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      CPUB (R28-7) - Body ground L-B - Body ground B (CPUB) power supply Always 10 to 14 V
      MPX1 (R28-6) - GND (R28-1) L - W-B MPX line Always 10 kΩ or higher
      GND (R28-1) - 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.

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