CAN COMMUNICATION SYSTEM(w/o Toyota Safety Sense) Check CAN Bus Line for Short to GND (LHD Models)

DESCRIPTION

There may be a short circuit between the CAN bus lines and GND when the resistance between terminals 6 (CANH) and 4 (CG) or terminals 14 (CANL) and 4 (CG) of the DLC3 is below 200 Ω.

Symptom Trouble Area
The resistance between terminals 6 (CANH) and 4 (CG) or terminals 14 (CANL) and 4 (CG) of the DLC3 is below 200 Ω.
  • Short between CAN bus lines and GND

  • ECM

  • Combination meter assembly

  • Center airbag sensor assembly

  • Skid control ECU (brake actuator assembly)

  • Main body ECU (multiplex network body ECU)

  • Power steering ECU assembly

  • Certification ECU (smart key ECU assembly)*1

  • Steering angle sensor (spiral cable sub-assembly)*2

  • Radio and display receiver assembly*3

  • Air conditioning amplifier assembly*4

  • Engine stop and start ECU*5

  • No. 1 junction connector

  • No. 2 junction connector


WIRING DIAGRAM

A0047EIE05
A0049XGE03

CAUTION / NOTICE / HINT

Note


  • Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.

  • After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If doors need to be opened in order to check connectors, open the doors and leave them open.

Tech Tips

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE


  1. CHECK SHORT TO GND IN CAN BUS WIRE (DLC3 BRANCH WIRE)


    1. Turn the ignition switch off.

    2. Disconnect the A61 and F82 No. 1 junction connectors.

    3. A00483IE02
      Text in Illustration
      *a Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F4-6 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F4-14 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  2. CONNECT CONNECTOR


    1. Reconnect the A61 and F82 No. 1 junction connectors.


    NEXT
  3. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR)


    1. Disconnect the F83 No. 2 junction connector.

    2. A00483IE02
      Text in Illustration
      *a Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F4-6 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F4-14 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  4. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)


    1. A004A6RE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-7 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-18 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  5. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)

    Tech Tips

    For vehicles without air conditioning system or PTC heater, go to step 6.


    1. A0049ZCE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-8 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-19 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  6. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - STEERING ANGLE SENSOR (SPIRAL CABLE SUB-ASSEMBLY))

    Tech Tips

    For vehicles without VSC, go to step 7.


    1. A0049BPE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-1 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-12 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  7. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

    Tech Tips

    For vehicles without entry and start system, go to step 8.


    1. A0046VZE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-3 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-14 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  8. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - RADIO AND DISPLAY RECEIVER ASSEMBLY)

    Tech Tips

    For vehicles without display, go to step 9.


    1. A0047B2E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-5 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-16 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  9. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR ASSEMBLY)


    1. A004AURE03
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-4 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-15 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  10. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)


    1. Disconnect the A61 and F82 No. 1 junction connectors.

    2. A0048RKE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-4 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-15 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  11. CONNECT CONNECTOR


    1. Reconnect the F83 No. 2 junction connector.


    NEXT
  12. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - ECM)


    1. A0048U8E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A61-9 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      A61-20 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  13. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)


    1. A0049UAE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A61-10 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      A61-21 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  14. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - ENGINE STOP AND START ECU)

    Tech Tips

    For vehicles without stop and start system, go to step 15.


    1. A0048YOE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-5 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-16 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  15. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - POWER STEERING ECU ASSEMBLY)


    1. A0048RIE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-2 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-13 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    NG
    OK
  16. CHECK SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))


    1. A0046VVE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-1 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-12 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  17. CHECK SHORT TO GND IN CAN BUS WIRE (COMBINATION METER ASSEMBLY MAIN WIRE)


    1. Disconnect the F1 combination meter assembly connector.

    2. A004A6RE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-7 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-18 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  18. CHECK SHORT TO GND IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER ASSEMBLY BRANCH WIRE)


    1. Disconnect the F42*1 or F41*2 air conditioning amplifier assembly connector.

      *1 : w/ Automatic Air Conditioning System

      *2 : w/ Manual Air Conditioning System or PTC Heater

    2. A0049ZCE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-8 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-19 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  19. CHECK SHORT TO GND IN CAN BUS WIRE (STEERING ANGLE SENSOR (SPIRAL CABLE SUB-ASSEMBLY) BRANCH WIRE)


    1. Disconnect the F30 steering angle sensor (spiral cable sub-assembly) connector.

    2. A0049BPE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-1 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-12 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  20. CHECK SHORT TO GND IN CAN BUS WIRE (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) BRANCH WIRE)


    1. Disconnect the F63 certification ECU (smart key ECU assembly) connector.

    2. A0046VZE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-3 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-14 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  21. CHECK SHORT TO GND IN CAN BUS WIRE (RADIO AND DISPLAY RECEIVER ASSEMBLY BRANCH WIRE


    1. Disconnect the F115 radio and display receiver assembly connector.

    2. A0047B2E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-5 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-16 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  22. CHECK SHORT TO GND IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)


    1. Disconnect the F16 center airbag sensor assembly connector.

    2. A004AURE03
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F83-4 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F83-15 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  23. CHECK SHORT TO GND IN CAN BUS WIRE (ECM MAIN WIRE)


    1. Disconnect the A58*1, A93*2, A108*3 or A59*4 ECM connector.

      *1: for 2NR-FKE

      *2: for 1KR-FE

      *3: for 1ND-TV with DPF

      *4: for 1ND-TV without DPF

    2. A0048U8E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A61-9 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      A61-20 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher
      Result
      Result Proceed to
      NG A
      OK (for 2NR-FKE) B
      OK (for 1KR-FE) C
      OK (for 1ND-TV with DPF) D
      OK (for 1ND-TV without DPF) E

    A
    B
    C
    D
    E
  24. CHECK SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) BRANCH WIRE)


    1. Disconnect the A78*1 or A79*2 skid control ECU (brake actuator assembly) connector.

      *1: for CVT

      *2: except CVT

    2. A0049UAE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A61-10 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      A61-21 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  25. CHECK SHORT TO GND IN CAN BUS WIRE (ENGINE STOP AND START ECU BRANCH WIRE)


    1. Disconnect the F131 engine stop and start ECU connector.

    2. A0048YOE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-5 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-16 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  26. CHECK SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY)


    1. Disconnect the F6 power steering ECU assembly connector.

    2. A0048RIE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-2 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-13 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG
  27. CHECK SHORT TO GND IN CAN BUS WIRE (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) BRANCH WIRE)


    1. Disconnect the F76 main body ECU (multiplex network body ECU) connector.

    2. A0046VVE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F82-1 (CANH) - F4-4 (CG) Ignition switch off 200 Ω or higher
      F82-12 (CANL) - F4-4 (CG) Ignition switch off 200 Ω or higher

    OK
    NG