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Terminals Of Ecu

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK GATEWAY ECU 
    1. Disconnect the E23 ECU connector.
      Fig 1: Identifying Gateway ECU Connector Terminal Identification - Multiplex Communication System
      GTY201680Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      BATT (E23-10) - Body ground B - Body ground Power supply (Back-up) Always 10 to 14 V
      IG (E23-1) - Body ground W - Body ground Power supply (IG) Ignition switch:
      OFF → ON (IG)      		 Below 1 V → 10 to 14 V
      ACC (E23-2) - Body ground R - Body ground Power supply (ACC) Ignition switch:
      OFF → ON (ACC)      		 Below 1 V → 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (E23-24) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPD1 (E23-3) - Body ground G - Body ground MPX line Always 10 kΩ or higher
      MPD2 (E23-12) - Body ground P - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  2. CHECK RAIN SENSOR 
    1. Disconnect the N3 ECU connector.
      Fig 2: Identifying Rain Sensor Connector Terminal Identification
      GTY201681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SIG (N3-1) - Body ground V - Body ground Power supply (IG) Ignition switch:
      OFF → ON (IG)      		 Below 1 V → 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ES (N3-3) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX (N3-2) - Body ground L - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  3. CHECK BODY ECU 
    1. Disconnect the II, IA, IE, IF, IM, IR and D6 ECU connectors.
      Fig 3: Identifying Body ECU Connector Terminal Identification
      GTY201226Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (II-9) - Body ground LG - Body ground (*1)
      G - Body ground (*2)      		 Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      ACC (II-3) - Body ground R - Body ground (*1)
      BE - Body ground (*2)      		 Power supply (ACC) Ignition switch:
      off → on (ACC)      		 Below 1 V → 10 to 14 V
      BATB (IA-1) - Body ground B - Body ground Power supply (Back-up) Always 10 to 14 V
      GSW (IE-8) G Airbag sensor communication signal Airbag sensor communication circuit -

      (*1): w/ Smart Key System

      (*2): w/o Smart Key System

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GSW (IE-8) G Airbag sensor communication signal Airbag sensor communication circuit -
      GND1 (IF-10) - Body ground W-B - Body ground Ground Always Below 1 Ω
      GND2 (IM-9) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX1 (IR-9) - Body ground B - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D6-21) - Body ground BR - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  4. CHECK A/C ECU 
    1. Disconnect the D37 ECU connector.
      Fig 4: Identifying A/C ECU Connector Terminal Identification
      GTY210455Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG+ (D37-21) - Body ground G - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      B (D37-1) - Body ground SB - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (D37-20) - Body ground B - Body ground Ground Always Below 1 Ω
      MPX+ (D37-30) - Body ground LG - Body ground (*1)
      B - Body ground (*2)      		 MPX line Always 10 kΩ or higher
      MPX- (D37-31) - Body ground L - Body ground MPX line Always 10 kΩ or higher

      (*1): w/ Smart Key System

      (*2): w/o Smart Key System

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  5. CHECK POWER SOURCE CONTROL ECU 
    1. Disconnect the D44 ECU connector.
      Fig 5: Identifying Power Source Control ECU Connector Terminal Identification
      GTY201682Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ACCD (D44-11) - Body ground R - Body ground Power supply (ACC) Ignition switch:
      off → on (ACC)      		 Below 1 V → 10 to 14 V
      AM1 (D44-33) - Body ground W - Body ground Power supply (Back-up) Always 10 to 14 V
      AM2 (D44-12) - Body ground L - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND2 (D44-6) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX1 (D44-7) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D44-24) - Body ground LG - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  6. CHECK CERTIFICATION ECU 
    1. Disconnect the D39 ECU connectors.
      Fig 6: Identifying Certification ECU Connector Terminal Identification
      GTY201683Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (D39-18) - Body ground Y - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      ACC (D39-19) - Body ground SB - Body ground Power supply (ACC) Ignition switch:
      off → on (ACC)      		 Below 1 V → 10 to 14 V
      +B1 (D39-1) - Body ground R - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      E (D39-17) - Body ground W - Body ground Ground Always Below 1 Ω
      MPX1 (D39-27) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D39-28) - Body ground V - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  7. CHECK COMBINATION SWITCH ECU 
    1. Disconnect the D13 ECU connector.
      Fig 7: Identifying Combination Switch ECU Connector Terminal Identification
      GTY206220Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (D13-2) - Body ground L - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      B (D13-1) - Body ground P - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      E (D13-5) - Body ground W - Body ground Ground Always Below 1 Ω
      MPX1 (D13-6) - Body ground BR - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D13-7) - Body ground R - Body ground (*1)
      B - Body ground (*2)      		 MPX line Always 10 kΩ or higher

      (*1): w/ Smart Key System

      (*2): w/o Smart Key System

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  8. CHECK POWER SEAT ECU 
    1. Disconnect the P13 and P14 ECU connectors.
      Fig 8: Identifying Power Seat ECU Connector Terminal Identification
      GTY195467Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IG (P13-4) - Body ground Y - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      +B (P14-5) - Body ground LG - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (P14-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX1 (P13-1) - Body ground LG - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  9. CHECK MEMORY MIRROR ECU (LH) 
    1. Disconnect the H1 ECU connector.
      Fig 9: Identifying Memory Mirror ECU Connector Terminal Identificaiton(LH)
      GTY188625Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SIG (H1-3) - Body ground GR - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      CPUB (H1-4) - Body ground W - Body ground Power supply (Back-up) Always 10 to 14 V
      BDR (H1-6) - Body ground W - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (H1-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX1 (H1-8) - Body ground BR - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  10. CHECK MEMORY MIRROR ECU (RH) 
    1. Disconnect the G1 ECU connector.
      Fig 10: Identifying Memory Mirror ECU Connector Terminal Identification (RH)
      GTY176330Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SIG (G1-3) - Body ground GR - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      CPUB (G1-4) - Body ground W - Body ground Power supply (Back-up) Always 10 to 14 V
      BDR (G1-6) - Body ground V - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (G1-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPX1 (G1-8) - Body ground B - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  11. CHECK FRONT CONTROLLER 
    1. Disconnect the 1E, 1H and 1G ECU connectors.
      Fig 11: Identifying Front Controller Connector Terminal Identification
      GTY171292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the specified terminals on the wire harness side connector.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      1E-2 - Body ground Y - Body ground Power supply (IG) Ignition switch:
      off → on (IG)      		 Below 1 V → 10 to 14 V
      1H-4 - Body ground LG - Body ground Power supply (Back-up) Always 10 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      1G-7 - Body ground Y - Body ground MPX line Always 10 kΩ or higher
      1G-8 - Body ground B - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  12. COMBINATION METER ECU 
    1. Disconnect the E30 ECU connector.
      Fig 12: Identifying E30 ECU Connector Terminal Identification
      GTY300177Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.
      VOLTAGE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      B2 (E30-1) - Body ground V - Body ground Battery Always 11 to 14 V
      B (E30-21) - Body ground L - Body ground Ignition switch signal Ignition switch off Below 1 V
      Ignition switch on (IG) 11 to 14 V
      IG+ (E30-22) - Body ground R - Body ground Ignition switch signal Ignition switch off Below 1 V
      Ignition switch on (IG) 11 to 14 V

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

    3. Measure the resistance according to the value(s) in the table below.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      MPX- (E30-13) - Body ground P - Body ground MPX line Always 10 kΩ or higher
      MPX+ (E30-33) - Body ground LG - Body ground MPX line Always 10 kΩ or higher
      ES (E30-39) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E2 (E30-40) - Body ground B - Body ground Ground Always Below 1 Ω

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  13. CHECK OPTION CONNECTOR 
    1. Disconnect the D16 ECU connector.
      Fig 13: Identifying D16 ECU Connector Terminal Identification
      GTY201685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance between the specified terminals on the wire harness side connector.
      RESISTANCE:

      Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      MPX+ (D16-1) - Body ground W - Body ground MPX line Always 10 kΩ or higher

      If the values do not conform to the conditions specified, there may be a malfunction on the wire harness side.

  14. AIRBAG SENSOR ASSEMBLY 
    Fig 14: Identifying Airbag Sensor Connector Terminal Identification
    GTY210095Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
    GSW (D23-18) G Airbag sensor communication signal Airbag sensor communication circuit -
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