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 one of the CAN bus lines and +B when there is resistance between terminals 6 (CANH) and 16 (BAT), or terminals 14 (CANL) and 16 (BAT), of the DLC3.
*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 SHORT TO +B IN CAN BUS WIRE (DLC3 SUB BUS LINE)
(a) Disconnect the cable from the negative (-) battery terminal.
Text in Illustration
(b) Disconnect the connector from the CAN junction connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3
OK -- Continue to next step.
2. CHECK SHORT TO +B IN 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 SHORT TO +B IN CAN BUS WIRE (NETWORK GATEWAY ECU)
OK -- Continue to next step.
3. CHECK SHORT TO +B IN 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 SHORT TO +B IN CAN BUS WIRE (ECM)
OK -- Continue to next step.
4. CHECK SHORT TO +B IN 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 SHORT TO +B IN CAN BUS WIRE (YAW RATE SENSOR)
OK -- Continue to next step.
5. CHECK SHORT TO +B IN 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 SHORT TO +B IN CAN BUS WIRE (STEERING ANGLE SENSOR)
OK -- Continue to next step.
6. CHECK SHORT TO +B IN 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 SHORT TO +B IN CAN BUS WIRE (SKID CONTROL ECU)
OK -- Continue to next step.
7. CHECK SHORT TO +B IN 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 SHORT TO +B IN CAN BUS WIRE (NAVIGATION ECU)
OK -- Continue to next step.
8. CHECK SHORT TO B+ IN 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 SHORT TO B+ IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY)
OK -- REPLACE CAN JUNCTION CONNECTOR
9. CHECK SHORT TO +B IN CAN BUS WIRE (NETWORK GATEWAY ECU)
(a) Disconnect the 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 SHORT TO +B IN 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 SHORT TO +B IN 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 SHORT TO +B IN 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 SHORT TO +B IN 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 SHORT TO +B IN 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 SHORT TO B+ IN 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