CAN COMMUNICATION SYSTEM Open in One Side of CAN Branch Line

DESCRIPTION

If 2 or more ECUs and/or sensors do not appear on the intelligent tester "CAN Bus Check" screen, one side of the CAN branch wire may be open (one side of the CANH [branch wire]/CANL [branch wire] of the ECU and/or sensor is open).

Symptom Trouble Area
2 or more ECUs and/or sensors do not appear on the intelligent tester "Bus Check" screen.

  • Brake actuator assembly (VSC ECU)*1

  • Brake actuator assembly (ABS ECU)*2

  • Parking brake with bracket actuator assembly (electric parking brake ECU)

  • Main body ECU (instrument panel junction block assembly)

  • Yaw rate sensor*1

  • Spiral cable sub-assembly (steering angle sensor)*1

  • Power steering ECU assembly

  • Air conditioning amplifier assembly

  • Certification ECU*3

  • Center airbag sensor assembly

  • Power management control ECU*3

WIRING DIAGRAM

A00DQP4E01
A00DR1CE01

INSPECTION PROCEDURE

Tech Tips


  • Perform the following inspection for the ECUs (sensors) which are not displayed on the intelligent tester. If a malfunction cannot be identified, perform the following inspections for the ECUs (sensors) connected to the CAN communication system.


  • Do not remove the combination meter assembly and ECM, as they are the end parts of the circuit. If removed, CAN communication will not be possible.


  • The open circuit confirmation of the combination meter assembly, ECM and main wire is performed in the Check CAN Bus Line procedure of "How to Proceed with Troubleshooting". This inspection only has procedures for checking for an open circuit on one side of the CAN branch wire.

PROCEDURE


  1. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (BRAKE ACTUATOR)


    1. Disconnect the A41*1 brake actuator assembly (ABS ECU) or A42*2 or A43*3 brake actuator assembly (VSC ECU) connector.


      • *1: w/o Vehicle Stability Control System

      • *2: w/ Vehicle Stability Control System (for Automatic Transaxle and Manual Transaxle)

      • *3: w/ Vehicle Stability Control System (for CVT)

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "ABS/VSC/TRAC" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "ABS/VSC/TRAC" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE ( ELECTRIC PARKING BRAKE ECU) Click here

    A

  2. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (BRAKE ACTUATOR BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. Measure the resistance according to the value(s) in the table below.

      A00DPSEE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Brake Actuator Assembly)

      		 *3 w/ Vehicle Stability Control System (for CVT)
      *2 w/ Vehicle Stability Control System (for Automatic Transaxle and Manual Transaxle) *4 w/o Vehicle Stability Control System
      Standard Resistance
      w/ Vehicle Stability Control System (for Automatic Transaxle and Manual Transaxle)
      Tester Connection Switch Condition Specified Condition
      A42-35 (CANH) - A42-14 (CANL) Ignition switch off 54 to 69 Ω
      w/ Vehicle Stability Control System (for CVT)
      Tester Connection Switch Condition Specified Condition
      A43-35 (CANH) - A43-14 (CANL) Ignition switch off 54 to 69 Ω
      w/o Vehicle Stability Control System
      Tester Connection Switch Condition Specified Condition
      A41-26 (CANH) - 41-15 (CANL) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (w/ Vehicle Stability Control System) A
      OK (w/o Vehicle Stability Control System) B
      NG C

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY (ABS ECU) Click here

    C

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (ABS AND TRACTION ACTUATOR)

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY (VSC ECU) Click here

  3. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE ( ELECTRIC PARKING BRAKE ECU)


    1. Disconnect the I1 parking brake with bracket actuator assembly (electric parking brake ECU) connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Electric Parking Brake" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Electric Parking Brake" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU) Click here

    A

  4. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE ( ELECTRIC PARKING BRAKE ECU BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DRM4E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Parking Brake with Bracket Actuator Assembly)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      I1-11 (CANH) - I1-23 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR ( ELECTRIC PARKING BRAKE ECU)

    OK

    REPLACE PARKING BRAKE WITH BRACKET ACTUATOR ASSEMBLY (ELECTRIC PARKING BRAKE ECU) Click here

  5. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU)


    1. Disconnect the D81 main body ECU (instrument panel junction block assembly) connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Main Body" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Main Body" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR) Click here

    A

  6. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DSOGE01
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to Main Body ECU)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D81-15 (CANH) - D81-16 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (MAIN BODY ECU)

    OK

    REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

  7. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR)

    Note

    For vehicles without a vehicle stability control system, go to "Check for Open in One Side of Branch Wire (Power Steering ECU)".


    1. Disconnect the D69 yaw rate sensor connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Yaw Rate / Deceleration Sensor" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Yaw Rate / Deceleration Sensor" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (SPIRAL CABLE) Click here

    A

  8. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DPIOE12
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Yaw Rate Sensor)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D69-2 (CANH) - D69-3 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (YAW RATE SENSOR)

    OK

    REPLACE YAW RATE SENSOR Click here

  9. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (SPIRAL CABLE)


    1. Disconnect the D71 spiral cable sub-assembly (steering angle sensor) connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Steering Angle Sensor" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Steering Angle Sensor" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU) Click here

    A

  10. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (SPIRAL CABLE BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DUXME01
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to Spiral Cable Sub-assembly)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D71-4 (CANH) - D71-3 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (SPIRAL CABLE)

    OK

    REPLACE SPIRAL CABLE SUB-ASSEMBLY (STEERING ANGLE SENSOR) Click here

  11. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU)


    1. Disconnect the D50 power steering ECU assembly connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "EPS" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "EPS" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER) Click here

    A

  12. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DTAFE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D50-1 (CANH) - D50-7 (CANL) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    C

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (POWER STEERING ECU)

    A

    REPLACE POWER STEERING ECU ASSEMBLY Click here

  13. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER)


    1. Disconnect the D47*1 or D101*2 air conditioning amplifier connector.


      • *1: for Automatic Air Conditioning System

      • *2: for Manual Air Conditioning System and w/o Air Conditioning System

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Air Conditioner" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Air Conditioner" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (CERTIFICATION ECU) Click here

    A

  14. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DTGWE01
      Text in Illustration
      *1 for Automatic Air Conditioning System
      *2 for Manual Air Conditioning System and w/o Air Conditioning System
      *3

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Resistance
      for Automatic Air Conditioning System
      Tester Connection Switch Condition Specified Condition
      D47-11 (CANH) - D47-12 (CANL) Ignition switch off 54 to 69 Ω
      for Manual Air Conditioning System and w/o Air Conditioning System
      Tester Connection Switch Condition Specified Condition
      D101-11 (CANH) - D101-12 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (AIR CONDITIONING AMPLIFIER)

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  15. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (CERTIFICATION ECU)

    Note

    For vehicles without an entry and start system, go to "Check for Open in One Side of CAN Branch Wire (Center Airbag Sensor)".


    1. Disconnect the D54 certification ECU connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Entry & Start / Wireless Tuner" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Entry & Start / Wireless Tuner" not displayed on the intelligent tester. B

    B

    CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER MANAGEMENT CONTROL ECU) Click here

    A

  16. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (CERTIFICATION ECU BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DTOEE01
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to Certification ECU)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D54-9 (CANH) - D54-10 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CERTIFICATION ECU)

    OK

    REPLACE CERTIFICATION ECU

  17. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER MANAGEMENT CONTROL ECU)


    1. Disconnect the D109 power management control ECU connector.

    2. Select "Bus Check" on the intelligent tester Click here.

      Result
      Result Proceed to
      "Power Management1" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Power Management1" not displayed on the intelligent tester. B

    B

    CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (CENTER AIRBAG SENSOR BRANCH WIRE) Click here

    A

  18. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER MANAGEMENT CONTROL ECU BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. A00DU8TE52
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to Power Management Control ECU)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D109-14 (CA1H) - D109-13 (CA1L) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (POWER MANAGEMENT CONTROL ECU)

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  19. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (CENTER AIRBAG SENSOR BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note


      • w/ Navigation System (for HDD):

        After the ignition switch is turned off, the HDD navigation system requires approximately a minute to record various types of memory and settings. As a result, after turning the ignition switch off, wait a minute or more before disconnecting the cable from the negative (-) battery terminal.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. Disconnect the D10 center airbag sensor assembly connector.

    3. A00DUZ4E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Center Airbag Sensor Assembly)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D10-13 (CANH) - D10-22 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CENTER AIRBAG SENSOR)

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY Click here