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Part 1





NETWORKING: CAN COMMUNICATION SYSTEM: Short to B+ in CAN Bus Line
- Short to B+ in CAN Bus Line

DESCRIPTION

There may be a short circuit between the CAN bus lines and +B when the resistance between terminals 6 (CANH) and 16 (BAT) or terminals 14 (CANL) and 16 (BAT) of the DLC3 is below 6 kOhms.





* *: 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:
* w/ Navigation System:
After the engine switch is turned off, the display and navigation module display 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 B+ IN CAN BUS WIRE (DLC3 BRANCH WIRE)

(a) Disconnect the G79 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 G79 No. 3 junction connector connector.

NEXT -- Continue to next step.

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

(a) Disconnect the G82 No. 1 junction connector connector.





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

Standard Resistance:





Text in Illustration





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

5. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - CERTIFICATION ECU)

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





Standard Resistance:





Text in Illustration





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

6. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - POWER MANAGEMENT CONTROL ECU)

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





Standard Resistance:





Text in Illustration





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

7. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - FOUR WHEEL DRIVE CONTROL ECU)

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





Standard Resistance:





Text in Illustration





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

8. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - ECM)

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





Standard Resistance:





Text in Illustration





NG -- CONNECT CONNECTOR

OK -- REPLACE NO. 1 JUNCTION CONNECTOR

9. CONNECT CONNECTOR

(a) Reconnect the G82 No. 1 junction connector connector.

NEXT -- Continue to next step.

10. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (CERTIFICATION ECU)

(a) Disconnect the G26 certification 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 CERTIFICATION ECU (CANH, CANL)

OK -- REPLACE CERTIFICATION ECU Removal

11. CONNECT CONNECTOR

(a) Reconnect the G82 No. 1 junction connector connector.

NEXT -- Continue to next step.

12. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (POWER MANAGEMENT CONTROL ECU)

(a) Disconnect the G39 power management control 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 POWER MANAGEMENT CONTROL ECU (CA1H, CA1L)

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

13. CONNECT CONNECTOR

(a) Reconnect the G82 No. 1 junction connector connector.

NEXT -- Continue to next step.

14. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (FOUR WHEEL DRIVE CONTROL ECU)

(a) Disconnect the G41 four wheel drive control 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 FOUR WHEEL DRIVE CONTROL ECU (CANH, CANL)

OK -- REPLACE 4 WHEEL DRIVE CONTROL ECU Removal

15. CONNECT CONNECTOR

(a) Reconnect the G82 No. 1 junction connector connector.

NEXT -- Continue to next step.

16. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECM)

(a) Disconnect the G45 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

17. CONNECT CONNECTOR

(a) Reconnect the G82 No. 1 junction connector connector.

NEXT -- Continue to next step.

18. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - NO. 1 JUNCTION CONNECTOR)

(a) Disconnect the G85 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. 2 JUNCTION CONNECTOR - NO. 1 JUNCTION CONNECTOR)
OK -- Continue to next step.

19. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR SIDE)

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





Standard Resistance:





Text in Illustration





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

20. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - DISPLAY AND NAVIGATION MODULE DISPLAY)

HINT
For vehicles without a navigation system, go to "Check for Short to B+ in CAN Bus Wire (No. 2 Junction Connector - Center Airbag Sensor)".

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





Standard Resistance:





Text in Illustration





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

21. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR)

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





Standard Resistance:





Text in Illustration





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

22. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - SPIRAL WITH SENSOR CABLE)

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





Standard Resistance:





Text in Illustration





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

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