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 and/or the DLC3 bus branch when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 70 Ohms or more.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
* Turn the engine switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
* Turn the engine switch off before inspecting CAN bus wires for a ground short.
* 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 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 DLC3

(a) Turn the engine switch off.

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

Standard Resistance:

Text in Illustration

NOTICE:
When the measured value is 133 Ohms or more and a CAN communication system DTC is output, there may be a fault besides disconnection of the DLC3 branch wire. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area How to Proceed With Troubleshooting.

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

2. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 1 J/C)

(a) Disconnect the CAN No. 1 J/C wire harness connector.

Text in Illustration

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

Standard Resistance:

Result:

B -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN NO. 1 J/C)

C -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 2 J/C)

A -- REPLACE CAN NO. 1 J/C

3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 2 J/C)

(a) Reconnect the CAN No. 1 J/C wire harness connector.

(b) Disconnect the CAN No. 2 J/C wire harness connector.

Text in Illustration

Result:

B -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN NO. 2 J/C)

C -- CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 3 J/C)

A -- REPLACE CAN NO. 2 J/C

4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN NO. 3 J/C)

(a) Reconnect the CAN No. 2 J/C wire harness connector.

(b) Disconnect the CAN No. 3 J/C wire harness connector.

Text in Illustration

Result:

B -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 1 J/C - CAN NO. 3 J/C)

C -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 J/C - CAN NO. 3 J/C)

A -- REPLACE CAN NO. 3 J/C

5. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN NO. 1 J/C)

(a) Reconnect the CAN No. 1 J/C wire harness connector.

(b) Disconnect the ECM connector.

Text in Illustration

Result:

B -- REPLACE ECM Removal

C -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 1 J/C - ECM)

A -- REPLACE ECM Removal

6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN NO. 2 J/C)

(a) Reconnect the CAN No. 2 J/C wire harness connector.

(b) Disconnect the gateway ECU connector.

Text in Illustration

NG -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 J/C - GATEWAY ECU)

OK -- REPLACE GATEWAY ECU Removal