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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 in the CAN main wire and/or CAN branch wire when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is below 54 Ohms.






WIRING DIAGRAM









INSPECTION PROCEDURE
NOTICE:
- Turn the ignition switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.
- 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 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 will help determine the cause of the malfunction.

PROCEDURE

1. CHECK FOR SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR CTR)
(a) Turn the ignition switch off.
(b) Disconnect the CAN junction connector CTR.
(c) Measure the resistance according to the value(s) in the table below.





Standard resistance:






Result:






D -- CHECK FOR SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR RH)
C -- CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER ECU MAIN WIRE)
B -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3
A -- Continue to next step.
2. CHECK FOR SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR CTR)
(a) Measure the resistance according to the value(s) in the table below.





Standard resistance:






Result:






D -- CHECK FOR SHORT IN CAN BUS WIRES (STEERING ANGLE SENSOR BRANCH WIRE)
C -- CHECK FOR SHORT IN CAN BUS WIRES (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)
B -- CHECK FOR SHORT IN CAN BUS WIRES (YAW RATE SENSOR BRANCH WIRE)
A -- Continue to next step.
3. CHECK FOR SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR CTR)
(a) Measure the resistance according to the value(s) in the table below.





Standard resistance:






Result:






C -- CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU BRANCH WIRE)
B -- CHECK FOR SHORT IN CAN BUS WIRES (POWER STEERING ECU BRANCH WIRE)
A -- REPLACE CAN JUNCTION CONNECTOR CTR
4. CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER ECU 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
5. CHECK FOR SHORT IN CAN BUS WIRES (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:






C -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CAN JUNCTION CONNECTOR CTR - CAN JUNCTION CONNECTOR RH)
B -- CHECK FOR SHORT IN CAN BUS WIRES (ECM MAIN WIRE)
A -- Continue to next step.
6. CHECK FOR SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR RH)
(a) Measure the resistance according to the value(s) in the table below.





Standard resistance:






Result:






D -- CHECK FOR SHORT IN CAN BUS WIRES (SKID CONTROL ECU BRANCH WIRE)
C -- CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER BRANCH WIRE)
B -- CHECK FOR SHORT IN CAN BUS WIRES (ACCESSORY GATEWAY BRANCH WIRE)
A -- REPLACE CAN JUNCTION CONNECTOR RH
7. CHECK FOR SHORT IN CAN BUS WIRES (ECM MAIN WIRE)




(a) Disconnect the ECM connector.




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






Result:






C -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (ECM MAIN WIRE)
B -- REPLACE ECM
A -- REPLACE ECM
8. CHECK FOR SHORT IN CAN BUS WIRES (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
9. CHECK FOR SHORT IN CAN BUS WIRES (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)
OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY
10. CHECK FOR SHORT IN CAN BUS WIRES (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
11. CHECK FOR SHORT IN CAN BUS WIRES (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
12. CHECK FOR SHORT IN CAN BUS WIRES (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 IN CAN BUS WIRES (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
14. CHECK FOR SHORT IN CAN BUS WIRES (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 (SKID CONTROL ECU BRANCH WIRE)
15. CHECK FOR SHORT IN CAN BUS WIRES (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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