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Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus ES 350. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the engine switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.
  1. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (DLC3 BRANCH WIRE) 
    1. Turn the engine switch off.
    2. Disconnect DLC3 branch wire connector E44 from the CAN No. 2 J/C "A" side (without earth terminal).
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
        Fig 1: Identifying DLC3 Branch Wire Connector Terminals
        G05254991Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 1 MΩ or higher
    4. Reconnect DLC3 branch wire connector E62 to the CAN No. 2 J/C "A" side (without earth terminal).
    Fig 2: Identifying DLC3 Connector Terminals
    G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE DLC3 BRANCH WIRE OR CONNECTOR 

    OK: Go to Next Step 

  2. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (CAN NO. 2 J/C SIDE) 
    1. Disconnect CAN main bus wire connector E42 from the CAN No. 2 J/C "A" side (without earth terminal).
      Fig 3: Identifying CAN Main Bus Wire Connector Terminals
      G05254993Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect the probes of an ohmmeter to terminals 6 (CANH) and 14 (CANL) of the DLC3.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 108 to 132 Ω
    Fig 4: Identifying DLC3 Connector Terminals
    G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to step  7

    NG: Go to Next Step 

  3. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (CAN NO. 2 J/C BRANCH WIRE) 
    1. Reconnect CAN main bus wire connector E42 to the CAN No. 2 J/C "A" side (without earth terminal).
    2. Connect the probes of an ohmmeter to terminals 6 (CANH) and 14 (CANL) of the DLC3.
    3. While observing the resistance value shown on the tester, disconnect connectors E43, E45, E46, and E47 from the CAN No. 2 J/C one by one until the resistance becomes normal (between 54 and 69 Ω).

      HINT:

      Disconnect the branch wire connectors other than those of the DLC3.

      Fig 5: Identifying DLC3 Connector Terminals
      G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 6: Connection Diagram Of Components Which Connected To CAN J/C
      G05254835Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 7: Identifying CAN No 2 Junction Connector Terminals
      G05254832Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WIRING COLOR REFERENCE

      CAN No. 2 J/C Connector ("A" side, without earth terminal) Connector Color Color (CAN-H Side) Color (CAN-L Side)
      CAN No. 1 Bus Wire (E42) White B W
      Main Body ECU (E43) White BR GR
      DLC3 (E44) White LG P
      WIRING COLOR REFERENCE

      CAN No. 2 J/C Connector ("B" side, without earth terminal) Connector Color Color (CAN-H Side) Color (CAN-L Side)
      Yaw Rate Sensor (E47) White O P
      Center Airbag Sensor (E45) White G Y
      Steering Angle Sensor (E46) White V P
      Combination Meter (E48) White B W
      NOTE: Do not reconnect the disconnected connectors until this inspection is complete because there may be a short in 2 or more branch wires.

      Result 

      RESULT REFERENCE

      Symptom Proceed to
      The resistance is still below 54 Ω when all the specified connectors are disconnected. (There are no shorts in the branch wires.) A
      The resistance becomes normal (between 54 and 69 Ω when a connector is disconnected. (There is a short in one or more of the branch wires.) B
    4. When there is a short in one or more of the branch wires:
      1. Reconnect all of the connectors to the CAN No. 2 J/ C, except for the one that was disconnected last (the short-circuited bus wire). Check that the resistance shown on the tester is normal (between 54 and 69 Ω) to confirm that there is a short in one branch wire only.

        HINT:

        • The connectors connected to the CAN No. 2 J/C can be distinguished according to the color of the communication bus wires and the shape of the connectors.
        • Reconnecting the connectors to non-specified positions on the CAN No. 2 J/C does not affect system operation. However, it is preferred to reconnect the connectors to their specified positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.

    B: Go to step  12

    A: Go to Next Step 

  4. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (COMBINATION METER ECU MAIN BUS WIRE) 
    1. Disconnect combination meter main bus wire connector E48 from the CAN No. 2 J/C "B" side (without earth terminal).
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
        Fig 8: Identifying Combination Meter Main Bus Wire Connector Terminals
        G05254998Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 108 to 132 Ω
    Fig 9: Identifying DLC3 Connector Terminals
    G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE CAN NO. 2 J/C 

    OK: Go to Next Step 

  5. RECONNECT CONNECTOR 
    1. Reconnect combination meter main bus wire connector E48 to the CAN No. 2 J/C "B" side (without earth terminal).
  6. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (COMBINATION METER) 
    1. Disconnect combination meter connector E19.
      Fig 10: Identifying Combination Meter Connector E19
      G05255000Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 108 to 132 Ω

      HINT:

      If the resistance changes to 1 MΩ or more when the connector is disconnected, there may be a short in the ECM.

      Fig 11: Identifying DLC3 Connector Terminals
      G05255001Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN NO. 1 BUS MAIN WIRE OR CONNECTOR (COMBINATION METER MAIN BUS WIRE) 

    OK: REPLACE COMBINATION METER  (See COMBINATION METER )

  7. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (CAN NO. 5 J/C - CAN NO. 2 J/C) 
    1. Reconnect CAN No. 2 J/C connector E42.
    2. Disconnect CAN No. 5 J/C connector E34.
      Fig 12: Disconnecting CAN No 5 J/C Connector E34
      G05255002Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 108 to 132 Ω
    Fig 13: Identifying DLC3 Connector Terminals
    G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN NO. 1 BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 J/C - CAN NO. 5 J/C) 

    OK: Go to Next Step 

  8. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (CAN NO. 5 J/C - CAN NO. 2 J/C) 
    1. Reconnect CAN No. 5 J/C connector E34.
    2. Disconnect CAN No. 5 J/C connector A26.
      Fig 14: Disconnecting CAN No 5 J/C Connector A26
      G05255004Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 108 to 132 Ω
    Fig 15: Identifying DLC3 Connector Terminals
    G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to step  10

    NG: Go to Next Step 

  9. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (CAN NO. 5 J/C WIRE) 
    1. Reconnect CAN No. 5 J/C connector A26.
    2. Disconnect CAN No. 5 J/C connector E34.
      Fig 16: Disconnecting CAN No 5 J/C Connector E34
      G05254834Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Destination Condition Specified Value
      E34-1 (CANH) - E34-7 (CANL) A/C amplifier Engine switch off More than 1 Ω
      E34-2 (CANH)*2 - E34-8 (CANL)*2 Gateway ECU*2 Engine switch off More than 1 Ω
      E34-5*1 (CANH) - E34-11*1 (CANL) Multi-display*1 Engine switch off More than 1 Ω
      HINT:
      • *1: with Navigation system
      • *2: with AFS, dynamic radar cruise control system or pre-collision system

    NG: Go to step  12

    OK: REPLACE CAN NO. 5 J/C 

  10. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (CAN NO. 5 J/C WIRE) 
    1. Disconnect CAN No. 5 J/C connector A26.
      Fig 17: Disconnecting CAN No 5 J/C Connector A26
      G05255007Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Destination Condition Specified Value
      A26-1 (CANH) - A26-7 (CANL) ECM Engine switch off 108 to 132 Ω
      A26-2 (CANH) - A26-8 (CANL) Skid control ECU Engine switch off More than 1 Ω
      A26-3 (CANH) - A26-9 (CANL) Active control engine mount ECU Engine switch off More than 1 Ω.

      Result 

      RESULT REFERENCE

      Result Proceed to
      OK A
      NG (Short in wires other than those connected to the ECM) B
      NG (Short in wires connected to the ECM) C

    A: REPLACE CAN NO. 5 J/C 

    B: Go to step  12

    C: Go to Next Step 

  11. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE (ECM MAIN BUS WIRE) 
    1. Disconnect ECM connector A10.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      A26-1 (CANH) - A26-7 (CANL) Engine switch off 1 MΩ or higher

      HINT:

      Measure the resistance with CAN No. 5 J/C connector A26 disconnected.

    Fig 18: Disconnecting CAN No 5 J/C Connector A26
    G05254986Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN NO. 1 BUS MAIN WIRE OR CONNECTOR (ECM - CAN NO. 5 J/ C) 

    OK: REPLACE ECM  (See ECM )

  12. RECONNECT CONNECTOR 
    1. Reconnect the connector for the short-circuited branch wire to the CAN No. 2 J/C or CAN No. 5 J/C (the connector that caused the bus wire resistance to become normal (between 54 and 69 Ω) when it was disconnected).
  13. CHECK FOR SHORT IN CAN NO. 1 BUS WIRE 
    1. Disconnect the connector that includes terminals CANH and CANL from the ECU (or sensor) to which the short-circuited branch wire is connected. (See PROBLEM SYMPTOMS TABLE  )
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Value
      E21-6 (CANH) - E21-14 (CANL) Engine switch off 1 MΩ or higher
      Fig 19: Identifying DLC3 Connector Terminals
      G05254978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      If the resistance becomes normal (between 54 and 69 Ω) when the connector is disconnected from the ECU (or sensor), there may be a short in the ECU (or sensor).

    NG: REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BRANCH WIRE OR CONNECTOR 

    OK: REPLACE CORRESPONDING ECU OR SENSOR 

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