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Inspection Procedure

  1. CHECK CAN BUS LINE (MAIN BUS LINE FOR DISCONNECTION, BUS LINES FOR SHORT CIRCUIT) 
    Fig 1: Identifying DLC3 Connector terminals
    G03003420Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch to the LOCK position.
    2. Measure the resistance according to the value (s) in the table below.

    Standard: 

    ECM CONNECTOR TERMINALS RESISTANCE

    Tester connection Condition Specified value Result
    D1-6 (CANH) - D1-14 (CANL) Ignition Switch OFF 54 to 69 Ω OK
    D1-6 (CANH) - D1-14 (CANL) Ignition Switch OFF 69 Ω or more (w/o LEXUS Navigation system) NG-A
    D1-6 (CANH) - D1-14 (CANL) Ignition Switch OFF 69 Ω or more (w/ LEXUS Navigation System) NG-B
    D1-6 (CANH) - D1-14 (CANL) Ignition Switch OFF 54 Ω or less (w/o LEXUS Navigation System) NG-C
    D1-6 (CANH) - D1-14 (CANL) Ignition Switch OFF 54 Ω or less (w/ LEXUS Navigation System) NG-D

    NG-A:  CHECK CAN MAIN BUS LINE FOR DISCONNECTION (W/O LEXUS NAVIGATION SYSTEM)  

    NG-B:  CHECK CAN MAIN BUS LINE FOR DISCONNECTION (W/ LEXUS NAVIGATION SYSTEM)  

    NG-C:  CHECK CAN BUS LINES FOR SHORT CIRCUIT (W/O LEXUS NAVIGATION SYSTEM)  

    NG-D:  CHECK CAN BUS LINES FOR SHORT CIRCUIT (W/ LEXUS NAVIGATION SYSTEM)  

    OK: GO TO NEXT STEP 

  2. CHECK CAN BUS LINE FOR SHORT TO +B 
    Fig 2: Identifying DLC3 Connector terminals
    G03003421Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance according to the value (s) in the table below.

    Standard: 

    ECM CONNECTOR TERMINALS RESISTANCE

    Tester Connection Condition Specified value
    D1-6 (CANH) - D1-16 (BAT) Ignition Switch OFF 1 MΩ or more
    D1-14 (CANL) - D1-16 (BAT) Ignition Switch OFF 1 MΩ or more

    HINT:

    • NG-A: w/o LEXUS Navigation System.
    • NG-B: w/ LEXUS Navigation System.

    NG-A:  CHECK CAN BUS LINE FOR SHORT TO +B (W/O LEXUS NAVIGATION SYSTEM)  

    NG-B:  CHECK CAN BUS LINE FOR SHORT TO +B (W/ LEXUS NAVIGATION SYSTEM)  

    OK: GO TO NEXT STEP 

  3. CHECK CAN BUS LINE FOR SHORT TO GND 
    Fig 3: Identifying DLC3 Connector terminals
    G03003422Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance according to the value (s) in the table below.

    Standard: 

    ECM CONNECTOR TERMINALS RESISTANCE

    Tester Connection Condition Specified value
    D1-4 (CG) - D1-6 (CANH) Ignition Switch OFF 1 kΩ or more
    D1-4 (CG) - D1-14 (CANL) Ignition Switch OFF 1 kΩ or more

    HINT:

    • NG-A: w/o LEXUS Navigation System.
    • NG-B: w/ LEXUS Navigation System.

    NG-A:  CHECK CAN BUS LINE FOR SHORT TO GND (W/O LEXUS NAVIGATION SYSTEM)  

    NG-B:  CHECK CAN BUS LINE FOR SHORT TO GND (W/ LEXUS NAVIGATION SYSTEM)  

    OK:  HOW TO PROCEED WITH TROUBLESHOOTING  

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