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Short to B+ in CAN Bus Line








CAN COMMUNICATION SYSTEM: Short to B+ in CAN Bus Line

Short to B+ in CAN Bus Line

DESCRIPTION

A short to +B is suspected in the CAN bus line when there is continuity between terminals 16 (BAT) and 6 (CANH) or terminals 16 (BAT) and 14 (CANL) of the DLC3.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK SHORT IN CAN BUS WIRES (DLC3 BRANCH WIRE)
(a) Disconnect the J9 CAN junction connector.




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






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CANH, CANL)
OK -- Continue to next step.

2. CONNECT CONNECTOR
(a) Reconnect the J9 CAN junction connector.
NEXT -- Continue to next step.

3. CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - SKID CONTROL ECU)




(a) Disconnect the J6 CAN junction connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - STEERING ANGLE SENSOR)
OK -- Continue to next step.

4. CHECK SHORT IN CAN BUS WIRES (SKID CONTROL ECU)




(a) Disconnect the S1 skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






Result





C -- REPLACE MASTER CYLINDER SOLENOID (SKID CONTROL ECU)
B -- REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU)
A -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO SKID CONTROL ECU (CANH, CANL)
5. CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - STEERING ANGLE SENSOR)




(a) Disconnect the J8 CAN junction connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - YAW RATE AND DECELERATION SENSOR)
OK -- Continue to next step.

6. CHECK SHORT IN CAN BUS WIRES (STEERING ANGLE SENSOR)




(a) Disconnect the S9 steering angle sensor connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO STEERING ANGLE SENSOR (CANH, CANL)
OK -- REPLACE STEERING ANGLE SENSOR
7. CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - YAW RATE AND DECELERATION SENSOR)




(a) Disconnect the J7 CAN junction connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - ECM)
OK -- Continue to next step.

8. CHECK SHORT IN CAN BUS WIRES (YAW RATE AND DECELERATION SENSOR)




(a) Disconnect the Y1 yaw rate and deceleration sensor connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO YAW RATE AND DECELERATION SENSOR (CANH, CANL)
OK -- REPLACE YAW RATE AND DECELERATION SENSOR
9. CHECK SHORT IN CAN BUS WIRES (CAN JUNCTION CONNECTOR - ECM)




(a) Disconnect the J10 CAN junction connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPLACE CAN JUNCTION CONNECTOR
OK -- Continue to next step.

10. CHECK SHORT IN CAN BUS WIRES (ECM)




(a) Disconnect the E7 or E14 ECM connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






Result





C -- REPLACE ECM
B -- REPLACE ECM
A -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (CANH, CANL)
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