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Short in CAN Bus Lines





CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Short in CAN Bus Lines
- Short in CAN Bus Lines

DESCRIPTION

There may be a short circuit between the CAN bus lines when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is below 54 Ohms.





HINT
* *1: w/ Bus Buffer ECU
* *2: w/ 4WD
* *3: w/ Power Steering ECU

WIRING DIAGRAM









INSPECTION PROCEDURE

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

PROCEDURE

1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

(a) 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 prevent airbag and seat belt pretensioner activation.

NEXT -- Continue to next step.

2. CHECK FOR SHORT IN CAN BUS WIRES (DLC3 BRANCH WIRE)

(a) Disconnect the J118 No. 1 junction connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CANH, CANL)
OK -- Continue to next step.

3. CONNECT CONNECTOR

(a) Reconnect the J118 No. 1 junction connector.

NEXT -- Continue to next step.

4. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR)

(a) Disconnect the J113 No. 2 junction connector.





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

Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)
OK -- Continue to next step.

5. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - AIR CONDITIONING AMPLIFIER)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER)
OK -- Continue to next step.

6. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - BUS BUFFER ECU)

NOTICE:
For vehicles without a bus buffer ECU, go to "CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - 4WD CONTROL ECU)".

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (BUS BUFFER ECU)
OK -- Continue to next step.

7. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - 4WD CONTROL ECU)

NOTICE:
For vehicles without 4-wheel drive, go to "CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - ECM)".

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (4WD CONTROL ECU)
OK -- Continue to next step.

8. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - ECM)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (ECM)

OK -- REPAIR OR REPLACE NO. 2 JUNCTION CONNECTOR

9. CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER)

(a) Disconnect the J19 air conditioning amplifier connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO AIR CONDITIONING AMPLIFIER (CANH, CANL)

OK -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal

10. CHECK FOR SHORT IN CAN BUS WIRES (BUS BUFFER ECU)

(a) Disconnect the J59 bus buffer ECU connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO BUS BUFFER ECU (CAN+, CAN-)

OK -- REPLACE BUS BUFFER ECU

11. CHECK FOR SHORT IN CAN BUS WIRES (4WD CONTROL ECU)

(a) Disconnect the A25 4WD control ECU connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO 4WD CONTROL ECU (CANH, CANL)

OK -- REPLACE 4WD CONTROL ECU

12. CHECK FOR SHORT IN CAN BUS WIRES (ECM)

(a) Disconnect the A24 ECM connector.





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

Standard resistance:





Result





E -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (CANH, CANL)

D -- REPLACE ECM Removal

C -- REPLACE ECM Removal

B -- REPLACE ECM Removal

A -- REPLACE ECM Removal

13. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)

(a) Disconnect the J118 No. 1 junction connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 1 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)
OK -- Continue to next step.

14. CONNECT CONNECTOR

(a) Reconnect the J113 No. 2 junction connector.

NEXT -- Continue to next step.

15. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - COMBINATION METER ECU)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER ECU)
OK -- Continue to next step.

16. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - MAIN BODY ECU)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)
OK -- Continue to next step.

17. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - SKID CONTROL ECU WITH ACTUATOR)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (SKID CONTROL ECU WITH ACTUATOR)
OK -- Continue to next step.

18. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - STEERING ANGLE SENSOR)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (STEERING ANGLE SENSOR)
OK -- Continue to next step.

19. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - POWER STEERING ECU)

NOTICE:
For vehicles without a power steering ECU, go to "CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR)".

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (POWER STEERING ECU)
OK -- Continue to next step.

20. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR)

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





Standard resistance:





NG -- CHECK FOR SHORT IN CAN BUS WIRES (CENTER AIRBAG SENSOR)

OK -- REPAIR OR REPLACE NO. 1 JUNCTION CONNECTOR

21. CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER ECU)

(a) Disconnect the J28 combination meter ECU connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO COMBINATION METER ECU (CANH, CANL)

OK -- REPLACE COMBINATION METER ASSEMBLY Removal

22. CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)

(a) Disconnect the J2 main body ECU connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO MAIN BODY ECU (CANH, CANL)

OK -- REPLACE MAIN BODY ECU

23. CHECK FOR SHORT IN CAN BUS WIRES (SKID CONTROL ECU WITH ACTUATOR)

(a) Disconnect the A17 skid control ECU with actuator connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO SKID CONTROL ECU WITH ACTUATOR (CANH, CANL)

OK -- REPLACE SKID CONTROL ECU WITH ACTUATOR Removal

24. CHECK FOR SHORT IN CAN BUS WIRES (STEERING ANGLE SENSOR)

(a) Disconnect the J6 steering angle sensor connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO STEERING ANGLE SENSOR (CANH, CANL)

OK -- REPLACE STEERING ANGLE SENSOR Removal

25. CHECK FOR SHORT IN CAN BUS WIRES (POWER STEERING ECU)

(a) Disconnect the J119 power steering ECU connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO POWER STEERING ECU (CANH, CANL)

OK -- REPLACE POWER STEERING ECU

26. CHECK FOR SHORT IN CAN BUS WIRES (CENTER AIRBAG SENSOR)

(a) Disconnect the J46 center airbag sensor connector.





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

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO CENTER AIRBAG SENSOR (CANH, CANL)

OK -- REPLACE CENTER AIRBAG SENSOR Removal
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