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Open in CAN Main Bus Line





NETWORKING: CAN COMMUNICATION SYSTEM: Open in CAN Main Bus Line
- Open in CAN Main Bus Line

DESCRIPTION

There may be an open circuit in the CAN main bus line and/or the DLC3 branch line when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 69 Ohms or more.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Turn the engine switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.
* After the engine 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 engine 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 engine switch, any switches, or any doors triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.

PROCEDURE

1. CHECK DLC3

(a) Turn the engine switch off.

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





Standard Resistance:





NOTICE:
When the measured value is 132 Ohms or more and a CAN communication system DTC is output, there may be a fault besides disconnection of the DLC3 branch line. For that reason, troubleshooting should be performed again from "How to Proceed with Troubleshooting" How to Proceed With Troubleshooting after repairing the trouble area.

B -- REPAIR OR REPLACE DLC3 BRANCH LINE OR CONNECTOR (CANH, CANL)
A -- Continue to next step.

2. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN BUS CHECK)

(a) Perform "CAN Bus Check" using the Techstream Diagnosis System.

Result:





B -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN RH JUNCTION CONNECTOR)

C -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR)
A -- Continue to next step.

3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR)

(a) Turn the engine switch off.





(b) Disconnect the ECM connector (A6).

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

Standard Resistance:





NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (ECM - CAN LH JUNCTION CONNECTOR)

OK -- REPLACE ECM Removal

4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN RH JUNCTION CONNECTOR)

(a) Turn the engine switch off.





(b) Disconnect the gateway ECU connector (J76).

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

Standard Resistance:





NG -- RECONNECT CONNECTOR

OK -- REPLACE GATEWAY ECU Removal

5. RECONNECT CONNECTOR

(a) Reconnect the gateway ECU connector (J76).

NEXT -- Continue to next step.

6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN RH JUNCTION CONNECTOR - GATEWAY ECU)

(a) Disconnect the CAN main bus line connector (J84) from the CAN RH junction connector B side (w/o earth terminal).





NOTICE:
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.

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

Standard Resistance:





NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN RH JUNCTION CONNECTOR - GATEWAY ECU)

OK -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN LH JUNCTION CONNECTOR - CAN RH JUNCTION CONNECTOR)

7. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR)

(a) Turn the engine switch off.





(b) Disconnect the ECM connector (A6).

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

Standard Resistance:





NG -- RECONNECT CONNECTOR

OK -- REPLACE ECM Removal

8. RECONNECT CONNECTOR

(a) Reconnect the ECM connector (A6).

NEXT -- Continue to next step.

9. CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN RH JUNCTION CONNECTOR)

(a) Disconnect the gateway ECU connector (J76).





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

Standard Resistance:





NG -- RECONNECT CONNECTOR

OK -- REPLACE GATEWAY ECU Removal

10. RECONNECT CONNECTOR

(a) Reconnect the gateway ECU connector (J76).

NEXT -- Continue to next step.

11. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN RH JUNCTION CONNECTOR - GATEWAY ECU)

(a) Disconnect the CAN main bus line connector (J84) from the CAN RH junction connector B side (w/o earth terminal).





NOTICE:
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.

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

Standard Resistance:





NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN RH JUNCTION CONNECTOR - GATEWAY ECU)
OK -- Continue to next step.

12. RECONNECT CONNECTOR

(a) Reconnect the CAN main bus line connector (J84) to the CAN RH junction connector B side (w/o earth terminal).

NEXT -- Continue to next step.

13. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR)

(a) Disconnect the CAN main bus line connector (J2) from the CAN LH junction connector A side (w/ earth terminal).





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

Standard Resistance:





NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (ECM - CAN LH JUNCTION CONNECTOR)

OK -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN LH JUNCTION CONNECTOR - CAN RH JUNCTION CONNECTOR)
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