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Check CAN Bus Line for Short to +B





CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Check CAN Bus Line for Short to +B
- Check CAN Bus Line for Short to +B

DESCRIPTION

There may be a short circuit between the CAN bus line and +B when no resistance exists between terminals 6 (CANH) and 16 (BAT) or terminals 14 (CANL) and 16 (BAT) of the DLC3.





WIRING DIAGRAM









INSPECTION PROCEDURE

NOTICE:
* Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.
* 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 the doors need to be opened in order to check the 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 FOR SHORT TO +B IN CAN BUS WIRE (CAN JUNCTION CONNECTOR CTR)

(a) Turn the ignition switch off, and disconnect negative battery terminal.

(b) Disconnect the CAN junction connector CTR.

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





Standard resistance:





Result:





B -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3

C -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (COMBINATION METER MAIN WIRE)

D -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (CAN JUNCTION CONNECTOR RH)
A -- Continue to next step.

2. CHECK FOR SHORT TO +B IN CAN BUS WIRE (CAN JUNCTION CONNECTOR CTR)

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





Standard resistance:





Result:





B -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (YAW RATE SENSOR BRANCH WIRE)

C -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)

D -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (STEERING ANGLE SENSOR BRANCH WIRE)
A -- Continue to next step.

3. CHECK FOR SHORT TO +B IN CAN BUS WIRE (CAN JUNCTION CONNECTOR CTR)

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





Standard resistance:





Result:





B -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (POWER STEERING ECU BRANCH WIRE)

C -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (MAIN BODY ECU BRANCH WIRE)

A -- REPLACE CAN JUNCTION CONNECTOR CTR

4. CHECK FOR SHORT TO +B IN CAN BUS WIRE (COMBINATION METER MAIN WIRE)

(a) Disconnect the combination meter 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 (COMBINATION METER MAIN WIRE)

OK -- REPLACE COMBINATION METER Removal

5. CHECK FOR SHORT TO +B IN CAN BUS WIRE (CAN JUNCTION CONNECTOR RH)

(a) Disconnect the CAN junction connector RH

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





HINT
The resistance must be measured after the CAN junction connector CTR is disconnected.

Standard resistance:





Result:





B -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (ECM MAIN WIRE)

C -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CAN JUNCTION CONNECTOR CTR - CAN JUNCTION CONNECTOR RH)
A -- Continue to next step.

6. CHECK FOR SHORT TO +B IN CAN BUS WIRE (CAN JUNCTION CONNECTOR RH)

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





Standard resistance:





Result:





B -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (ACCESSORY GATEWAY BRANCH WIRE)

C -- CHECK FOR SHORT TO +B IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER BRANCH WIRE)

D -- CHECK SHORT TO +B IN CAN BUS WIRE (SKID CONTROL ECU BRANCH WIRE)

A -- REPLACE CAN JUNCTION CONNECTOR RH

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

(a) Disconnect the ECM connector.





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





Standard resistance:





Result:





B -- REPLACE ECM Removal

C -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (ECM MAIN WIRE)

A -- REPLACE ECM Removal

8. CHECK FOR SHORT TO +B IN CAN BUS WIRE (YAW RATE SENSOR BRANCH WIRE)

(a) Disconnect the yaw rate sensor connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (YAW RATE SENSOR BRANCH WIRE)

OK -- REPLACE YAW RATE SENSOR Removal

9. CHECK FOR SHORT TO +B IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)

(a) Disconnect the center airbag sensor assembly connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

10. CHECK FOR SHORT TO +B IN CAN BUS WIRE (STEERING ANGLE SENSOR BRANCH WIRE)

(a) Disconnect the steering angle sensor connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (STEERING ANGLE SENSOR BRANCH WIRE)

OK -- REPLACE STEERING ANGLE SENSOR Removal

11. CHECK FOR SHORT TO +B IN CAN BUS WIRE (POWER STEERING ECU BRANCH WIRE)

(a) Disconnect the power steering ECU connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (POWER STEERING ECU BRANCH WIRE)

OK -- REPLACE POWER STEERING ECU Removal

12. CHECK FOR SHORT TO +B IN CAN BUS WIRE (MAIN BODY ECU BRANCH WIRE)

(a) Disconnect the main body ECU connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (MAIN BODY ECU BRANCH WIRE)

OK -- REPLACE MAIN BODY ECU

13. CHECK FOR SHORT TO +B IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER BRANCH WIRE)

(a) Disconnect the air conditioning amplifier connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (AIR CONDITIONING AMPLIFIER BRANCH WIRE)

OK -- REPLACE AIR CONDITIONING AMPLIFIER Removal

14. CHECK SHORT TO +B IN CAN BUS WIRE (SKID CONTROL ECU BRANCH WIRE)

(a) Disconnect the skid control ECU connector.





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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (SKID CONTROL ECU BRANCH WIRE)

OK -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

15. CHECK FOR SHORT TO +B IN CAN BUS WIRE (ACCESSORY GATEWAY BRANCH WIRE)

(a) Disconnect the accessory gateway connector.

HINT
When accessories not connect it, repair or replace the accessory gateway branch wire or connector.

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





Standard resistance:





NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (ACCESSORY GATEWAY BRANCH WIRE)

OK -- CHECK AND REPLACE THE ACCESSORY
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