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Short in CAN Bus Lines





NETWORKING: 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.





* *: w/ Navigation System

WIRING DIAGRAM









INSPECTION PROCEDURE

HINT
Operating the engine 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 disable the SRS system.

NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected Repair Instruction - Initialization

NEXT -- Continue to next step.

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

(a) Disconnect the E75 No. 3 junction connector connector.





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

Standard Resistance:





Text in Illustration





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

3. CONNECT CONNECTOR

(a) Reconnect the E75 No. 3 junction connector connector.

NEXT -- Continue to next step.

4. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR SIDE)

(a) Disconnect the E72 No. 1 junction connector connector.





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

Standard Resistance:





Text in Illustration





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. 1 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR)

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





Standard Resistance:





Text in Illustration





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

6. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - ECM)

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





Standard Resistance:





Text in Illustration





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

OK -- REPAIR OR REPLACE NO. 1 JUNCTION CONNECTOR

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

(a) Disconnect the E47 center airbag sensor connector.





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

Standard Resistance:





Text in Illustration





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

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

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

(a) Disconnect the A38 ECM connector.





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

Standard Resistance:





Text in Illustration





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

OK -- REPLACE ECM Removal

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

(a) Disconnect the E69 No. 2 junction connector connector.





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

Standard Resistance:





Text in Illustration





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

10. CONNECT CONNECTOR

(a) Reconnect the E72 No. 1 junction connector connector.

NEXT -- Continue to next step.

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





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

Standard Resistance:





Text in Illustration





NG -- CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NO. 3 JUNCTION CONNECTOR)
OK -- Continue to next step.

12. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - MULTI-DISPLAY)

HINT
For vehicles without the navigation system, go to "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:





Text in Illustration





NG -- CHECK FOR SHORT IN CAN BUS WIRES (DISPLAY AND NAVIGATION MODULE DISPLAY)
OK -- Continue to next step.

13. 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:





Text in Illustration





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

14. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NETWORK GATEWAY ECU)

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





Standard Resistance:





Text in Illustration





NG -- CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU)

OK -- REPAIR OR REPLACE NO. 2 JUNCTION CONNECTOR

15. CHECK FOR SHORT IN CAN BUS WIRES (DISPLAY AND NAVIGATION MODULE DISPLAY)

(a) Disconnect the F47 display and navigation module display connector.





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

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DISPLAY AND NAVIGATION MODULE DISPLAY (CANH, CANL)

OK -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY Removal

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

(a) Disconnect the E35 air conditioning amplifier connector.





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

Standard Resistance:





Text in Illustration





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

OK -- REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Removal

17. CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU)

(a) Disconnect the E31 network gateway ECU connector.





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

Standard Resistance:





Text in Illustration





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

OK -- REPLACE NETWORK GATEWAY ECU Removal

18. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NO. 3 JUNCTION CONNECTOR)

(a) Disconnect the E75 No. 3 junction connector connector.





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

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 2 JUNCTION CONNECTOR - NO. 3 JUNCTION CONNECTOR)
OK -- Continue to next step.

19. CONNECT CONNECTOR

(a) Reconnect the E69 No. 2 junction connector connector.

NEXT -- Continue to next step.

20. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - MAIN BODY ECU)

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





Standard Resistance:





Text in Illustration





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

21. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - COMBINATION METER)

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





Standard Resistance:





Text in Illustration





NG -- CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER)

OK -- REPAIR OR REPLACE NO. 3 JUNCTION CONNECTOR

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

(a) Disconnect the E3 main body ECU (cowl side junction block LH) connector.





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

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) (CANH, CANL)

OK -- REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)

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

(a) Disconnect the E7 combination meter connector.





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

Standard Resistance:





Text in Illustration





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

OK -- REPLACE COMBINATION METER ASSEMBLY Removal
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