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Short to GND in CAN Bus Line





CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Short to GND in CAN Bus Line
- Short to GND in CAN Bus Line

DESCRIPTION

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





HINT
*1: w/ Multi-display

*2: w/o Multi-display

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 prevent airbag and seat belt pretensioner activation.

NOTICE:
* w/ Navigation System (for HDD):
After the engine switch is turned off, the display and navigation module display (HDD navigation system) records various types of memory and settings. As a result, after turning the engine switch off, be sure to wait for the time specified in the following table before disconnecting the cable from the negative (-) battery terminal.

Waiting Time before Disconnecting Cable from Negative (-) Battery Terminal:





* 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 TO GND IN CAN BUS WIRE (DLC3 BRANCH WIRE)

(a) Disconnect the L97 No. 2 junction connector connector.





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

Result





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

3. CONNECT CONNECTOR

(a) Reconnect the L97 No. 2 junction connector connector.

NEXT -- Continue to next step.

4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR SIDE)

(a) Disconnect the A67 No. 1 junction connector connector.





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

Result





NG -- CONNECT CONNECTOR
OK -- Continue to next step.

5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - SKID CONTROL ECU)

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU)
OK -- Continue to next step.

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

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM)

OK -- REPAIR OR REPLACE NO. 1 JUNCTION CONNECTOR

7. CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU)

(a) Disconnect the A21 skid control ECU connector.





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

Result





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

OK -- REPLACE SKID CONTROL ECU Removal

8. CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM)

(a) Disconnect the A13 ECM connector.





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

Result





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

OK -- REPLACE ECM Removal

9. CONNECT CONNECTOR

(a) Reconnect the A67 No. 1 junction connector connector.

NEXT -- Continue to next step.

10. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR SIDE)

(a) Disconnect the L98 No. 3 junction connector connector.





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

Result





NG -- CONNECT CONNECTOR
OK -- Continue to next step.

11. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR - AFS ECU)

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (AFS ECU)
OK -- Continue to next step.

12. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR - DISPLAY AND NAVIGATION MODULE DISPLAY)

NOTICE:
For vehicles without multi-display, go to "CHECK CAN BUS LINE FOR SHORT TO GND (NO. 3 JUNCTION CONNECTOR - INTEGRATION CONTROL AND PANEL ASSEMBLY)".

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





Result





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

13. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR - INTEGRATION CONTROL AND PANEL ASSEMBLY)

NOTICE:
For vehicles with multi-display, go to "CHECK CAN BUS LINE FOR SHORT TO GND (NO. 3 JUNCTION CONNECTOR - ELECTRIC POWER CONTROL ECU)".

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (INTEGRATION CONTROL AND PANEL ASSEMBLY)
OK -- Continue to next step.

14. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR - ELECTRIC POWER CONTROL ECU)

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (ELECTRIC POWER CONTROL ECU)
OK -- Continue to next step.

15. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR - AIR CONDITIONING AMPLIFIER)

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





Result





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

16. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 3 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR)

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTER AIRBAG SENSOR)

OK -- REPAIR OR REPLACE NO. 3 JUNCTION CONNECTOR

17. CHECK FOR SHORT TO GND IN CAN BUS WIRE (AFS ECU)

(a) Disconnect the A37 AFS ECU connector.





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

Result





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

OK -- REPLACE AFS ECU Removal

18. CHECK FOR SHORT TO GND IN CAN BUS WIRE (DISPLAY AND NAVIGATION MODULE DISPLAY)

(a) Disconnect the L59 display and navigation module display connector.





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

Result





B -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY Removal

C -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY Removal

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

A -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY Removal

19. CHECK FOR SHORT TO GND IN CAN BUS WIRE (INTEGRATION CONTROL AND PANEL ASSEMBLY)

(a) Disconnect the L35 integration control and panel connector.





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

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO INTEGRATION CONTROL AND PANEL ASSEMBLY (CANH, CANL)

OK -- REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY Removal

20. CHECK FOR SHORT TO GND IN CAN BUS WIRE (ELECTRIC POWER CONTROL ECU)

(a) Disconnect the A69 electric power control ECU connector.





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

Result





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

OK -- REPLACE ELECTRIC POWER CONTROL ECU

21. CHECK FOR SHORT TO GND IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER)

(a) Disconnect the L77 air conditioning amplifier connector.





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

Result





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

OK -- REPLACE AIR CONDITIONING AMPLIFIER Removal

22. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTER AIRBAG SENSOR)

(a) Disconnect the L73 center airbag sensor connector.





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

Result





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

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

23. CONNECT CONNECTOR

(a) Reconnect the L98 No. 3 junction connector connector.

NEXT -- Continue to next step.

24. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - MAIN BODY ECU)

(a) Disconnect the L97 No. 2 junction connector connector.





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

Result





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

25. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - NO. 1 METER ECU)

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





Result





NG -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 METER ECU)

OK -- REPAIR OR REPLACE NO. 2 JUNCTION CONNECTOR

26. CHECK FOR SHORT TO GND IN CAN BUS WIRE (MAIN BODY ECU)

(a) Disconnect the L11 main body ECU connector.





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

Result





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

OK -- REPLACE MAIN BODY ECU

27. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 METER ECU)

(a) Disconnect the L10 No. 1 meter ECU connector.





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

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO NO. 1 METER ECU (CANH, CANL)

OK -- REPLACE COMBINATION METER ASSEMBLY (NO. 1 METER ECU SUB-ASSEMBLY) Disassembly
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