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 "Bus Check" screen, one side of the CAN branch wire may be open (one side of the CANH [CAN branch wire]/CANL [CAN 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 (skid control ECU)

  • Certification ECU (smart key ECU assembly)*1

  • Air conditioning amplifier assembly*2

  • Spiral with sensor cable sub-assembly (steering angle sensor)

  • Yaw rate sensor

  • Main body ECU (instrument panel junction block assembly)

  • Center airbag sensor assembly

  • Power management control ECU*1

  • Power steering ECU assembly

  • Radio and display receiver assembly*3

  • Engine stop and start ECU*4

  • Driving support ECU assembly*5


WIRING DIAGRAM

A01IP2DE01
A01IPJ4E01
A01IOP6E01

INSPECTION PROCEDURE

Note


  • For vehicles with an entry and start system:

    Before replacing the certification ECU (smart key ECU assembly), refer to the entry and start system (for Entry Function) Click here.

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

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 ASSEMBLY)


    1. Disconnect the A52*1 or A54*2 brake actuator assembly (skid control ECU) connector.


      • *1: for 1AD-FTV, 2AD-FHV, 1WW

      • *2: for 1ZR-FAE, 2ZR-FAE

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

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

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


    1. A01IQ6CE13
      Text in Illustration
      *A for 1AD-FTV, 2AD-FTV, 1WW
      *B for 1ZR-FAE, 2ZR-FAE
      *a

      Front view of wire harness connector

      (to Brake Actuator Assembly)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      for 1AD-FTV, 2AD-FHV, 1WW
      Tester Connection Switch Condition Specified Condition
      A52-35 (CANH) - A52-14 (CANL) Ignition switch off 54 to 69 Ω
      for 1ZR-FAE, 2ZR-FAE
      Tester Connection Switch Condition Specified Condition
      A54-35 (CANH) - A54-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  3. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (ENGINE STOP AND START ECU)

    Note

    For vehicles without a stop and start system, go to "Check for Open in One Side of CAN Branch Wire (Main Body ECU)".


    1. Disconnect the H121 engine stop and start ECU connector.

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

      Result
      Result Proceed to
      "Stop and Go/Start" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Stop and Go/Start" not displayed on the intelligent tester. B

    B
    A
  4. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (ENGINE STOP AND START ECU CAN BRANCH WIRE)


    1. A01IOU5E22
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Engine Stop and Start ECU)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H121-15 (CANH) - H121-16 (CANL) Ignition switch off 54 to 69 Ω

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


    1. Disconnect the H81 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
    A
  6. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU CAN BRANCH WIRE)


    1. A01IN0UE05
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Main Body ECU [Instrument Panel Junction Block Assembly])

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H81-15 (CANH) - H81-16 (CANL) Ignition switch off 54 to 69 Ω

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


    1. Disconnect the H68 yaw rate sensor connector.

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

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

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


    1. A01IPT7E18
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Yaw Rate Sensor)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H68-2 (CANH) - H68-3 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  9. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY)


    1. Disconnect the H69 spiral with sensor cable sub-assembly (steering angle sensor) connector.

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

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

    B
    A
  10. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY CAN BRANCH WIRE)


    1. A01IPSCE38
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Spiral with Sensor Cable Sub-assembly)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H69-4 (CANH) - H69-3 (CANL) Ignition switch off 54 to 69 Ω

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


    1. Disconnect the H49 power steering ECU assembly connector.

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

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

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


    1. A01IRTBE07
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H49-2 (CANH) - H49-8 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  13. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (RADIO AND DISPLAY RECEIVER ASSEMBLY)

    Note

    For vehicles without a radio and display receiver type, go to "Check for Open in One Side of CAN Branch Wire (Air Conditioning Amplifier Assembly)".


    1. Disconnect the H105 radio and display receiver assembly connector.

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

      Result
      Result Proceed to
      "Display and Navigation (AVN1)" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Display and Navigation (AVN1)" not displayed on the intelligent tester. B

    B
    A
  14. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (RADIO AND DISPLAY RECEIVER ASSEMBLY CAN BRANCH WIRE)


    1. A01ISS8E16
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Radio and Display Receiver Assembly)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H105-9 (CANH) - H105-10 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  15. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER ASSEMBLY)

    Note

    For vehicles with an entry and start system, go to "Check for Open in One Side of CAN Branch Wire (Certification ECU)".


    1. Disconnect the H46*1, H9*2 or H118*3 air conditioning amplifier assembly connector.


      • *1: for Automatic Air Conditioning System

      • *2: except 1WW (for Manual Air Conditioning System or w/o Air Conditioning System)

      • *3: for 1WW (for Manual Air Conditioning System or w/o Air Conditioning System)

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

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

    B
    A
  16. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER ASSEMBLY CAN BRANCH WIRE)


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

      A01ITCZE04
      Text in Illustration
      *A for Automatic Air Conditioning System *B except 1WW (for Manual Air Conditioning System or w/ o Air Conditioning System)
      *C for 1WW (for Manual Air Conditioning System or w/o Air Conditioning System) - -
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      - -

      CAUTION:

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

      Note

      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.

      Standard Resistance
      for Automatic Air Conditioning System
      Tester Connection Switch Condition Specified Condition
      H46-11 (CANH) - H46-12 (CANL) Ignition switch off 54 to 69 Ω
      except 1WW (for Manual Air Conditioning System or w/o Air Conditioning System)
      Tester Connection Switch Condition Specified Condition
      H9-2 (CANH) - H9-3 (CANL) Ignition switch off 54 to 69 Ω
      for 1WW (for Manual Air Conditioning System or w/o Air Conditioning System)
      Tester Connection Switch Condition Specified Condition
      H118-8 (CANH) - H118-9 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  17. 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 (Driving Support ECU Assembly)".


    1. Disconnect the H51 certification ECU (smart key ECU assembly) connector.

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

      Result
      Result Proceed to
      "Certification (Smart)" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Certification (Smart)" not displayed on the intelligent tester. B

    B
    A
  18. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (CERTIFICATION ECU CAN BRANCH WIRE)


    1. A01ISYUE44
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Certification ECU [Smart Key ECU Assembly])

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H51-9 (CANH) - H51-10 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  19. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (DRIVING SUPPORT ECU ASSEMBLY)

    Note

    For vehicles without a 1WW engine type and cruise control system, go to "Check for Open in One Side of CAN Branch Wire (Power Management Control ECU)".


    1. Disconnect the H124 driving support ECU assembly connector.

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

      Result
      Result Proceed to
      "Driving Support (Cruise Control-ACC)" not displayed on the intelligent tester. A
      Several ECUs and sensors in addition to "Driving Support (Cruise Control-ACC)" not displayed on the intelligent tester. B

    B
    A
  20. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (DRIVING SUPPORT ECU ASSEMBLY CAN BRANCH WIRE)


    1. A01IQQLE18
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Driving Support ECU)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H124-39 (CA2H) - H124-17 (CA2L) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B
    C
    A
  21. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER MANAGEMENT CONTROL ECU)


    1. Disconnect the H71 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
    A
  22. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER MANAGEMENT CONTROL ECU CAN BRANCH WIRE)


    1. A01IOSCE97
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

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

      CAUTION:

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

      Note

      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.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H71-14 (CA1H) - H71-13 (CA1L) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B
    C
    A
  23. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE (CENTER AIRBAG SENSOR ASSEMBLY CAN BRANCH WIRE)


    1. A01IRRWE23
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Center Airbag Sensor Assembly)

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

      CAUTION:

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

      Note

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

    2. Disconnect the center airbag sensor assembly connector Click here.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H19-13 (CANH) - H19-22 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK