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Check CAN Bus Lines for Short Circuit





CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Check CAN Bus Lines for Short Circuit
- Check CAN Bus Lines for Short Circuit

DESCRIPTION

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





*1: w/ Navigation system

WIRING DIAGRAM









INSPECTION PROCEDURE

NOTICE:
* Turn the ignition switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
* Turn the ignition switch off before inspecting CAN bus wires for a ground short.
* After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
* 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 any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT
* Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
* Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE

1. CHECK CAN BUS WIRE (DLC3 SUB BUS LINE)

(a) Turn the ignition switch off.

(b) Disconnect the connector from CAN junction connector.

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE DLC3 SUB BUS LINE OR CONNECTOR
OK -- Continue to next step.

2. CHECK CAN BUS WIRE (NETWORK GATEWAY ECU SUB BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (NETWORK GATEWAY ECU)
OK -- Continue to next step.

3. CHECK CAN BUS WIRE (ECM MAIN BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (ECM)
OK -- Continue to next step.

4. CHECK CAN BUS WIRE (YAW RATE SENSOR SUB BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (YAW RATE SENSOR)
OK -- Continue to next step.

5. CHECK CAN BUS WIRE (STEERING ANGLE SENSOR SUB BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (STEERING ANGLE SENSOR)
OK -- Continue to next step.

6. CHECK CAN BUS WIRE (SKID CONTROL ECU MAIN BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (SKID CONTROL ECU)
OK -- Continue to next step.

7. CHECK CAN BUS WIRE (NAVIGATION ECU SUB BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (NAVIGATION ECU)
OK -- Continue to next step.

8. CHECK CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY SUB BUS LINE)

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





Text in Illustration





Standard resistance:





NG -- CHECK CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY)

OK -- REPLACE JUNCTION CONNECTOR (CAN J/C)

9. CHECK CAN BUS WIRE (NETWORK GATEWAY ECU)

(a) Disconnect the network gateway ECU connector (E23).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE NETWORK GATEWAY ECU SUB BUS LINE OR CONNECTOR

OK -- REPLACE NETWORK GATEWAY ECU

10. CHECK CAN BUS WIRE (ECM)

(a) Disconnect the ECM connector (A55).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE ECM MAIN BUS LINE OR CONNECTOR

OK -- REPLACE ECM Removal

11. CHECK CAN BUS WIRE (YAW RATE SENSOR)

(a) Disconnect the yaw rate sensor connector (D28).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE YAW RATE SENSOR SUB BUS LINE OR CONNECTOR

OK -- REPLACE YAW RATE AND ACCELERATION SENSOR Removal

12. CHECK CAN BUS WIRE (STEERING ANGLE SENSOR)

(a) Disconnect the steering angle sensor connector (D12).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE STEERING ANGLE SENSOR SUB BUS LINE OR CONNECTOR

OK -- REPLACE STEERING ANGLE SENSOR Removal

13. CHECK CAN BUS WIRE (SKID CONTROL ECU)

(a) Disconnect the skid control ECU connector (A34).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE SKID CONTROL ECU MAIN BUS LINE OR CONNECTOR

OK -- REPLACE SKID CONTROL ECU Removal

14. CHECK CAN BUS WIRE (NAVIGATION ECU)

(a) Disconnect the navigation ECU connector (E54).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE NAVIGATION ECU SUB BUS LINE OR CONNECTOR

OK -- REPLACE NAVIGATION ECU Removal

15. CHECK CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY)

(a) Disconnect the center airbag sensor assembly connector (D23).

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





Text in Illustration





Standard resistance:





NG -- REPAIR OR REPLACE CENTER AIRBAG SENSOR ASSEMBLY SUB BUS LINE OR CONNECTOR

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY