Short to GND in CAN Bus Line

CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Short to GND in CAN Bus Line

Short to GND in CAN Bus Line

DESCRIPTION

There may be a short circuit between the CAN bus line and GND when there is resistance between terminals 6 (CANH) and 4 (CG) or terminals 14 (CANL) and 4 (CG) of the DLC3.





HINT: *: w/ dynamic radar cruise control system.

WIRING DIAGRAM





INSPECTION PROCEDURE
NOTICE:
Turn the power switch OFF before measuring the resistances of the main wire and the branch wire.
HINT: Operating the power switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE

1. CHECK CAN BUS LINE FOR SHORT TO GND (DLC3 BRANCH WIRE)




(a) Disconnect the K86 CAN junction connector center connector.
(b) Measure the resistance of the DLC3.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CANH, CANL)
OK -- Continue to next step.
2. CONNECT CONNECTOR
(a) Reconnect the K86 CAN junction connector center connector.
NEXT -- Continue to next step.
3. CHECK CAN BUS LINE FOR SHORT TO GND (CAN JUNCTION CONNECTOR RR)




(a) Disconnect the V37 CAN junction connector RR connector.
(b) Measure the resistance of the DLC3.

Result





OK -- CHECK CAN BUS LINE FOR SHORT TO GND (SEAT BELT CONTROL ECU)
NG -- Continue to next step.
4. CONNECT CONNECTOR
(a) Reconnect the V37 CAN junction connector RR connector.
NEXT -- Continue to next step.
5. CHECK CAN BUS LINE FOR SHORT TO GND (CAN JUNCTION CONNECTOR, CENTER - NETWORK GATEWAY ECU)




(a) Disconnect the K84 CAN junction connector center connector.
(b) Measure the resistance of the DLC3.

Result





OK -- CHECK CAN BUS LINE FOR SHORT TO GND (NETWORK GATEWAY ECU)
NG -- Continue to next step.
6. CHECK CAN BUS LINE FOR SHORT TO GND (CAN JUNCTION CONNECTOR CENTER - CLEARANCE WARNING ECU)




(a) Disconnect the K88 CAN junction connector center connector.
(b) Measure the resistance of the DLC3.

Result





OK -- CHECK CAN BUS LINE FOR SHORT TO GND (CLEARANCE WARNING ECU)
NG -- Continue to next step.
7. CHECK CAN BUS LINE FOR SHORT TO GND (CAN JUNCTION CONNECTOR CENTER - DISTANCE CONTROL ECU)
NOTICE:
For vehicles without dynamic radar cruise control system, go to "CHECK CAN BUS LINE FOR SHORT TO +B (CAN JUNCTION CONNECTOR CENTER - ECM)".




(a) Disconnect the K85 CAN junction connector center connector.
(b) Measure the resistance of the DLC3.

Result





OK -- CHECK CAN BUS LINE FOR SHORT TO GND (DISTANCE CONTROL ECU)
NG -- Continue to next step.
8. CHECK CAN BUS LINE FOR SHORT TO GND (CAN JUNCTION CONNECTOR CENTER - HYBRID VEHICLE CONTROL ECU)




(a) Disconnect the K83 CAN junction connector center connector.
(b) Measure the resistance of the DLC3.

Result





OK -- CHECK CAN BUS LINE FOR SHORT TO GND (HYBRID VEHICLE CONTROL ECU)
NG -- REPAIR OR REPLACE CAN JUNCTION CONNECTOR CENTER
9. CHECK CAN BUS LINE FOR SHORT TO GND (NETWORK GATEWAY ECU)




(a) Disconnect the K66 network gateway ECU connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- REPLACE CAN BRANCH WIRE CONNECTED TO NETWORK GATEWAY ECU (CANH, CANL)
OK -- REPLACE NETWORK GATEWAY ECU
10. CHECK CAN BUS LINE FOR SHORT TO GND (CLEARANCE WARNING ECU)




(a) Disconnect the A38 clearance warning ECU connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO CLEARANCE WARNING ECU (CANH, CANL)
OK -- REPLACE CLEARANCE WARNING ECU
11. CHECK CAN BUS LINE FOR SHORT TO GND (DISTANCE CONTROL ECU)




(a) Disconnect the K13 distance control ECU connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DISTANCE CONTROL ECU (CANH, CANL)
OK -- REPLACE DISTANCE CONTROL ECU
12. CHECK CAN BUS LINE FOR SHORT TO GND (HYBRID VEHICLE CONTROL ECU)




(a) Disconnect the A54 hybrid vehicle control ECU connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO HYBRID VEHICLE CONTROL ECU (CANH, CANL)
OK -- REPLACE HYBRID VEHICLE CONTROL ECU
13. CHECK CAN BUS LINE FOR SHORT TO GND (SEAT BELT CONTROL ECU)




(a) Disconnect the V38 CAN junction connector RR connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- CHECK CAN BUS LINE FOR SHORT TO GND (SEAT BELT CONTROL ECU)
OK -- Continue to next step.
14. CHECK CAN BUS LINE FOR SHORT TO GND (CAN JUNCTION CONNECTOR RR - ECM)




(a) Disconnect the V37 CAN junction connector RR connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- CHECK CAN BUS LINE FOR SHORT TO GND (ECM)
OK -- REPAIR OR REPLACE CAN JUNCTION CONNECTOR RR
15. CHECK CAN BUS LINE FOR SHORT TO GND (SEAT BELT CONTROL ECU)




(a) Disconnect the V43 seat belt control ECU connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO SEAT BELT CONTROL ECU (CANH, CANL)
OK -- REPLACE SEAT BELT CONTROL ECU
16. CHECK CAN BUS LINE FOR SHORT TO GND (ECM)




(a) Disconnect the A53 ECM connector.
(b) Measure the resistance of the wire harness side connectors.

Result





NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (CANH, CANL)
OK -- REPLACE ECM