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Terminals Of Ecu

  1. CHECK NETWORK GATEWAY ECU 
    Fig 1: Identifying G3 ECU Connector Terminals
    G05294401Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the G3 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINALS VOLTAGE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (G3-24) - Body ground W-B - Body ground Ground Always Below 1 Ω
      BATT (G3-10) - GND (G3-22) B - W-B +B (BATT) power supply Always 10 to 14 V
      MPD1 (G3-3) - Body ground P-L - Body ground MPX line Always 10 kΩ or higher
      MPD2 (G3-12) - Body ground R-L - Body ground MPX line Always 10 kΩ or higher
      MPI1 (G3-4) - Body ground L-O - Body ground MPX line Always 10 kΩ or higher
      MPI2 (G3-13) - Body ground Y - Body ground MPX line Always 10 kΩ or higher
      MPL1 (G3-5) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      MPL2 (G3-14) - Body ground B-R - 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.

  2. CHECK DRIVER SIDE JUNCTION BLOCK (DRIVER SIDE JUNCTION BLOCK ECU) 
    Fig 2: Identifying D2 And D4 ECU Connectors Terminals
    G05294402Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the D2 and D4 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND2 (D4-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX-B (D4-5) - GND (2G-8) L-B - W-B +B (MPX-B) power supply Always 10 to 14 V
      MPX1 (D2-15) - Body ground L-Y - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D4-7) - Body ground W-L - Body ground MPX line Always 10 kΩ or higher
      MPX3 (D4-6) - Body ground G - 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.

  3. CHECK PASSENGER SIDE JUNCTION BLOCK (PASSENGER SIDE JUNCTION BLOCK ECU) 
    Fig 3: Identifying 3E, 3G And 3H Junction Block And P4 And P6 ECU Connectors Terminal
    G05294403Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the 3E, 3G and 3H junction block connectors.
    2. Disconnect the P4 and P6 ECU connectors.
    3. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (3G-8) - Body ground W-B - Body ground Ground Always Below 1 Ω
      GND1 (P4-11) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX-B (3E-16) - GND (3G-8) B - W-B +B (MPX-B) power supply Always 10 to 14 V
      AIRBAG (3H-2) - Body ground R-L - Body ground MPX line Always 10 kΩ or higher
      MPX- (P6-4) - Body ground Y - 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.

  4. CHECK LUGGAGE ROOM JUNCTION BLOCK (LUGGAGE ROOM JUNCTION BLOCK ECU) 
    Fig 4: Identifying 6F, 6J Junction Block And L24 ECU Connectors Terminal
    G05294404Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the 6F and 6J junction block connectors.
    2. Disconnect the L24 ECU connector.
    3. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SG (L24-5) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX-B (6F-12) - P-GND (6A-5) L-B - W-B +B (MPX-B) power supply Always 10 to 14 V
      MPX+ (L24-2) - Body ground B - Body ground MPX line Always 10 kΩ or higher
      MPX- (L24-13) - Body ground R - 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.

  5. CHECK MULTIPLEX NETWORK FRONT DOOR ECU LH 
    Fig 5: Identifying D17 And D19 ECU Connectors
    G05294405Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the D17 and D19 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (D19-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      CPUB (D19-4) - GND (C1) L-O - W-B +B (CPUB) power supply Always 10 to 14 V
      BDR (D19-6) - GND (D19-1) B-R - W-B +B (BDR) power supply Always 10 to 14 V
      MPX1 (D17-22) - Body ground R-L - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D17-30) - Body ground O - 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.

  6. CHECK MULTIPLEX NETWORK FRONT DOOR ECU RH 
    Fig 6: Identifying P9 And P11 ECU Connectors
    G05294406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P9 and P11 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (P11-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      CPUB (P11-4) - GND (P11-1) L-O - W-B +B (CPUB) power supply Always 10 to 14 V
      BDR (P11-6) - GND (P11-1) G-Y - W-B +B (BDR) power supply Always 10 to 14 V
      MPX1 (P9-22) - Body ground R-L - Body ground MPX line Always 10 kΩ or higher
      MPX2 (P9-30) - Body ground B-Y - 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.

  7. CHECK TIRE PRESSURE MONITOR RECEIVER ASSEMBLY 
    Fig 7: Identifying T9 ECU Connector
    G05294407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T9 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (T9-6) - Body ground W-B - Body ground Ground Always Below 1 Ω
      +B (T9-1) - GND (T9-6) B - W-B +B power supply Always 10 to 14 V
      MPX1 (T9-2) - Body ground L-O - Body ground MPX line Always 10 kΩ or higher
      MPX2 (T9-3) - Body ground R-L - 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.

  8. CHECK THEFT WARNING ECU 
    Fig 8: Identifying T7 ECU Connector
    G05294408Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T7 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (T7-20) - Body ground W-B - Body ground Ground Always Below 1 Ω
      +B2 (T7-21) - GND (T7-20) B-O - W-B +B (+B2) power supply Always 10 to 14 V
      MPX (T7-13) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      MPX2 (T7-33) - Body ground BR - 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.

  9. CHECK TRANSPONDER KEY ECU 
    Fig 9: Identifying T13 ECU Connector
    G05294409Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T13 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal inscription Condition Specified Condition
      GND (T13-14) - Body ground W-B - Body ground Ground Always Below 1 Ω
      CPUB (T13-1) - GND (T13-14) L-O - W-B +B (CPUB) power supply Always 10 to 14 V
      MPX1 (T13-4) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      MPX2 (T13-5) - Body ground P-L - 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.

  10. CHECK TURN SIGNAL SWITCH ASSEMBLY 
    Fig 10: Identifying C11 Switch Connector
    G05294410Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C11 switch connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      E (C11-8) - Body ground W-B - Body ground Ground Always Below 1 Ω
      B (C11-1) - E (C11-8) L-B - W-B +B (B) power supply Always 10 to 14 V
      MPX1 (C11-9) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      MPX2 (C11-10) - Body ground B - 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.

  11. CHECK MULTIPLEX NETWORK FRONT LIGHT ECU 
    Fig 11: Identifying Multiplex Network Front Light ECU Relay
    G05294411Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the voltage and resistance of the connectors.
      NOTE: The inspection should be performed from the backside of the relay block with the multiplex network front light ECU connector connected.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (12) - Body ground W-B - Body ground Ground Always Below 1 Ω
      FMB3 (8) - GND (12) L-B - W-B +B (FMB3) power supply Always 10 to 14 V
      MPX1 (5) - Body ground B-R - Body ground MPX line Always 10 kΩ or higher
      MPX2 (6) - Body ground W-L - 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.

  12. CHECK STEERING PAD SWITCH MODULATOR 
    Fig 12: Identifying C10 Modulator Connector
    G05294412Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C10 modulator connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ECC (C10-4) - Body ground BR - Body ground Ground Always Below 1 Ω
      +B (C10-2) - ECC (C10-4) B-O - BR
      • +B power supply
      • Ground
      		 Always 10 to 14 V
      MPX (C10-3) - Body ground G - 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.

  13. CHECK MULTIPLEX TILT AND TELESCOPIC ECU 
    Fig 13: Identifying T8 ECU Connector
    G05294413Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T8 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (T8-4) - Body ground W-B - Body ground Ground Always Below 1 Ω
      ECUB (T8-5) - GND (T8-4) L-B - W-B +B (ECU) power supply Always 10 to 14 V
      +B (T8-10) - GND (T8-4) L-W - W-B +B power supply Always 10 to 14 V
      MPX1 (T8-7) - Body ground W-L - Body ground MPX line Always 10 kΩ or higher
      MPX2 (T8-6) - Body ground V - 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 COMBINATION METER ASSEMBLY 
    Fig 14: Identifying C8 Meter Connector
    G05294414Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C8 meter connector.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ES (C8-12) - Body ground BR - Body ground Ground Always Below 1 Ω
      +B (C8-13) - ES (C8-12) B - BR +B power supply Always 10 to 14 V
      MPX+ (C8-3) - Body ground Y - Body ground MPX line Always 10 kΩ or higher
      MPX- (C8-4) - Body ground L-O - 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.

  15. CHECK SKID CONTROL ECU 
    Fig 15: Identifying S5, S6, S7 And S8 ECU Connectors
    G05294415Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S5, S6, S7 and S8 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND1 (S8-31) - Body ground W-B - Body ground Ground Always Below 1 Ω
      GND2 (S8-6) - Body ground W-B - Body ground Ground Always Below 1 Ω
      GND3 (S5-22) - Body ground W-B - Body ground Ground Always Below 1 Ω
      GND4 (S5-16) - Body ground W-B - Body ground Ground Always Below 1 Ω
      IG1 (S7-6) - GND1 (S8-31) R - W-B Ignition (IG1) power supply Ignition switch ON 10 to 14 V
      IG2 (S6-6) - GND1 (S8-31) G-B - W-B Ignition (IG2) power supply Ignition switch ON 10 to 14 V
      MPX1 (S6-17) - Body ground L-O - Body ground MPX line Always 10 kΩ or higher
      MPX2 (S7-3) - Body ground R-L - 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.

  16. CHECK A/C AMPLIFIER ASSEMBLY 
    Fig 16: Identifying A9 And A10 ECU Connectors
    G05294416Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A9 and A10 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (A10-14) - Body ground W-B - Body ground Ground Always Below 1 Ω
      +B (A10-8) - GND (A10-14) W-R - W-B +B power supply Always 10 to 14 V
      IG (A10-1) - GND (A10-14) V-W - W-B Ignition (IG+) power supply Ignition switch ON 10 to 14 V
      MPX+ (A10-13) - Body ground L-O - Body ground MPX line Always 10 kΩ or higher
      MPX- (A9-10) - Body ground R-L - 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.

  17. CHECK SLIDING ROOF CONTROL ECU 
    Fig 17: Identifying S18 And S19 ECU Connectors
    G05294417Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S18 and S19 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      E1 (S18-6) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E2 (S19-9) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E3 (S19-10) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E4 (S19-11) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E5 (S18-5) - Body ground W-B - Body ground Ground Always Below 1 Ω
      SGND (S18-19) - Body ground BR - Body ground Ground Always Below 1 Ω
      CPUB (S19-8) - E1 (S18-6) L-O - W-B
      • +B (CPUB) power supply
      • GND
      		 Always 10 to 14 V
      MPX1 (S18-7) - Body ground B-Y - Body ground MPX line Always 10 kΩ or higher
      MPX2 (S18-1) - Body ground G - 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.

  18. CHECK POSITION CONTROL ECU (DRIVER SEAT ECU) 
    Fig 18: Identifying P21 And P22 ECU Connectors
    G05294418Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P21 and P22 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND1 (P22-7) - Body ground W-B - Body ground Ground Always Below 1 Ω
      +B (P22-8) - GND (P22-7) L-W - W-B +B power supply Always 10 to 14 V
      SYSB (P21-9) - GND (P22-7) L-O - W-B +B (SYSB) power supply Always 10 to 14 V
      MPX1 (P21-10) - Body ground P-L - Body ground MPX line Always 10 kΩ or higher
      MPX2 (P21-11) - Body ground R-L - 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.

  19. CHECK POSITION CONTROL ECU (PASSENGER SEAT ECU) 
    Fig 19: Identifying P23 And P24 ECU Connectors
    G05294419Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P23 and P24 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (P24-7) - Body ground W-B - Body ground Ground Always Below 1 Ω
      +B (P24-8) - GND (P22-7) L-W - W-B +B power supply Always 10 to 14 V
      SYSB (P23-9) - GND (P24-7) L-O - W-B +B (SYSB) power supply Always 10 to 14 V
      MPX1 (P23-10) - Body ground G - Body ground MPX line Always 10 kΩ or higher
      MPX2 (P23-11) - Body ground P-L - 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.

  20. CHECK AFS ECU 
    Fig 20: Identifying A31 ECU Connector
    G05294420Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A31 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      VOLTAGE AND RESISTANCE SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (A31-2) - Body ground R-L - Body ground +B (+B) power supply Ignition switch ON 10 to 14 V
      MPX1 (A31-5) - Body ground W-L - Body ground MPX line Always 10 kΩ or higher
      MPX2 (A31-6) - Body ground L-Y - Body ground MPX line Always 10 kΩ or higher
      E1 (A31-1) - 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.

  21. CHECK AIRBAG ECU 
    1. Refer to the airbag system (see TERMINALS OF ECU ).
  22. CHECK RADIO RECEIVER ASSEMBLY 
    1. Refer to the audio system (see TERMINALS OF ECU ).
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