CAN COMMUNICATION SYSTEM (for LHD) > CAN Bus Line

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DESCRIPTION

When any DTC for the CAN communication system is output, first measure the resistance between the terminals of the DLC3 to specify the trouble area. Then check that there is no short in the CAN main bus line, between the CAN bus lines, to +B, or to GND.

WIRING DIAGRAM


C115370E01


INSPECTION PROCEDURE

1.CHECK CAN BUS LINE (MAIN BUS LINE FOR DISCONNECTION, BUS LINES FOR SHORT CIRCUIT)

  1. Turn the ignition switch off.



    G026206E35

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

    Result:
    Tester Connection
    		Condition
    		Specified Value
    		Proceed to
    D1-6 (CANH) - D1-14 (CANL)
    		Disconnect the negative auxiliary battery cable
    		54 to 69 Ω
    		OK
    D1-6 (CANH) - D1-14 (CANL)
    		Disconnect the negative auxiliary battery cable
    		69 Ω or higher
    		NG-A
    D1-6 (CANH) - D1-14 (CANL)
    		Disconnect the negative auxiliary battery cable
    		54 Ω or less
    		NG-B



NG-A
CHECK CAN MAIN BUS LINE (FOR DISCONNECTION)

NG-B
CHECK CAN BUS LINE (FOR SHORT CIRCUIT)
OK


2.CHECK CAN BUS LINE (FOR SHORT TO +B)


    G026206E36

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Value
    D1-6 (CANH) - D1-16 (BAT)
    		Disconnect the negative auxiliary battery cable
    		1 MΩ or higher
    D1-14 (CANL) - D1-16 (BAT)
    		Disconnect the negative auxiliary battery cable
    		1 MΩ or higher



NG
CHECK CAN BUS LINE (FOR SHORT TO +B)
OK


3.CHECK CAN BUS LINE (FOR SHORT TO GND)


    G026206E37

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Value
    D1-4 (CG) - D1-6 (CANH)
    		Disconnect the negative auxiliary battery cable
    		1 kΩ or higher
    D1-4 (CG) - D1-14 (CANL)
    		Disconnect the negative auxiliary battery cable
    		1 kΩ or higher



NG
CHECK CAN BUS LINE (FOR SHORT TO GND)
OK

PROCEED TO ‘HOW TO PROCEED WITH TROUBLESHOOTING’