Short to GND in CAN Bus Line

CAN COMMUNICATION SYSTEM: Short to GND in CAN Bus Line

Short to GND in CAN Bus Line

DESCRIPTION

A short to GND is suspected in the CAN bus wire when the resistance between terminals 4 (CG) and 6 (CANH), or terminals 4 (CG) and 14 (CANL) of the DLC3 is below 200 Ohms.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTE: Turn the ignition switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.

PROCEDURE

1. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN BUS MAIN WIRE)
(a) Turn the ignition switch off.
(b) Disconnect the CAN junction connector.





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





Result:





C -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU)
B -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM)
A -- Continue to next step.
2. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN BUS BRANCH WIRE)





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





Result:





D -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (YAW RATE SENSOR BRANCH WIRE)
C -- CHECK FOR SHORT TO GND IN CAN BUS WIRE (STEERING ANGLE SENSOR)
B -- REPAIR OR REPLACE DLC3 BRANCH WIRE OR CONNECTOR
A -- REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN JUNCTION CONNECTOR)
3. CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM)





(a) Disconnect the ECM connector (E5).





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





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM
4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU)





(a) Disconnect the skid control ECU connector (S1).





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





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE SKID CONTROL ECU WITH ACTUATOR
5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (STEERING ANGLE SENSOR)





(a) Disconnect the steering angle sensor connector (S12).





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





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE STEERING ANGLE SENSOR
6. CHECK FOR SHORT TO GND IN CAN BUS WIRE (YAW RATE SENSOR BRANCH WIRE)





(a) Disconnect the yaw rate sensor connector (Y1).





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





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE YAW RATE SENSOR