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Check CAN Bus Lines for Short Circuit [10/2015 - ]: Procedure

  1. CHECK FOR SHORT IN CAN BUS LINES (DLC3 BRANCH LINE) 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the D75 DLC3 branch line connector.
      GTY571911Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 1 CAN Junction Connector)
      *b to DLC3
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    3. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *1 DLC3

    Result: 

    NG 

    REPAIR OR REPLACE CAN BRANCH LINE CONNECTED TO DLC3 

    Result: 

    OK 

    See step  2

  2. CHECK FOR SHORT IN CAN BUS LINES (BRANCH LINE) 
    1. Reconnect the D75 DLC3 branch line connector.
    2. Connect the probes of an ohmmeter to terminals 6 (CANH) and 14 (CANL) of the DLC3.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 DLC3
    3. While observing the resistance value shown on the tester, disconnect the D74, D76, D79, D83, D84, D112, D113, D114, D115 and D130 connectors from the No. 1 CAN junction connector or No. 2 CAN junction connector one by one until the resistance becomes normal (between 54 and 69 Ω).

      HINT: 

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

      GTY586149Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 DLC3 *2 Skid Control ECU (Brake Booster with Master Cylinder Assembly)
      *3 Steering Sensor *4 Tire Pressure Warning ECU and Receiver
      *5 Main Body ECU (Multiplex Network Body ECU) *6 Combination Meter Assembly
      *7 Hybrid Vehicle Control ECU Assembly *8 Power Steering ECU Assembly
      *9 Airbag ECU Assembly *10 Certification ECU (Smart Key ECU Assembly)
      *11 ECM *12 Air Conditioning Amplifier Assembly
      *13 Navigation ECU Sub-assembly (for Navigation Receiver Type)
      Radio and Display Receiver Assembly (for Radio and Display Type)      		 *14 No. 1 CAN Junction Connector
      *15 No. 2 CAN Junction Connector - -
      GTY609483Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (No. 1 CAN Junction Connector)      		 - -
      WIRING COLOR

      No. 1 CAN Junction Connector Side Code Color (CANH Side) Color (CANL Side)
      CAN main bus line (bus line connecting No. 1 CAN junction connector and No. 2 CAN junction connector) D72 B W
      Combination meter assembly D73 R W
      Main body ECU (Multiplex network body ECU) D74 P W
      DLC3 D75 L W
      Steering sensor D76 V W
      Hybrid vehicle control ECU assembly D114 G W
      Skid control ECU (Brake booster with master cylinder assembly) D115 Y W
      Tire Pressure Warning ECU and Receiver D130 SB W
      GTY577743Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (No. 2 CAN Junction Connector)      		 - -
      WIRING COLOR

      No. 2 CAN Junction Connector Side Code Color (CANH Side) Color (CANL Side)
      • Navigation ECU sub-assembly*1
      • Radio and display receiver assembly*2
      		 D84 R W
      CAN main bus line (bus line connecting No. 1 CAN junction connector and No. 2 CAN junction connector) D78 B W
      Air conditioning amplifier assembly D79 BR W
      ECM D81 P W
      Certification ECU (Smart key ECU assembly) D83 L W
      Airbag ECU assembly D113 LG W
      Power steering ECU assembly D112 G W
      • *1: for Navigation receiver type
      • *2: for Radio and display type
      NOTE:

      Do not reconnect the disconnected connectors until this inspection is complete because there may be a short in 2 or more branch lines.

      Result

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

        HINT: 

        • Connectors that connect to the CAN junction connector can be distinguished by the color of their CAN bus lines.
        • Reconnecting the connectors to non-original positions on the CAN junction connector does not affect system performance. However, it is preferred to reconnect the connectors to their original positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.

    Result: 

    B 

    See step  7

    Result: 

    A 

    See step  3

  3. CHECK FOR SHORT IN CAN BUS LINES (COMBINATION METER ASSEMBLY MAIN BUS LINE) 
    1. Disconnect the D73 combination meter assembly main bus line connector.
      GTY595974Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 1 CAN Junction Connector)
      *b to Combination Meter Assembly
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    2. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *1 DLC3

      Result

      Symptom Proceed to
      The resistance is still below 54 Ω when the combination meter assembly connector is disconnected. (There are no shorts in the combination meter assembly or between its main bus lines.) A
      The resistance falls within the specified range (between 108 and 132 Ω) (the other terminating resistor is normal) when the combination meter assembly connector is disconnected. (There is a short in the combination meter assembly or between its main bus lines.) B

    Result: 

    B 

    See step  8

    Result: 

    A 

    See step  4

  4. CHECK FOR SHORT IN CAN BUS LINES (ECM MAIN BUS LINE) 
    1. Disconnect the D81 ECM main bus line connector.
      GTY584979Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 2 CAN Junction Connector)
      *b to ECM
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    2. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *1 DLC3

      HINT: 

      Measure the resistance with the D73 combination meter assembly main bus line connector disconnected.

      Result

      Symptom Proceed to
      The resistance is still below 1 MΩ when the ECM connector is disconnected. (There are no shorts in the ECM or between its main bus lines.) A
      The resistance becomes 1 MΩ or more when the ECM connector is disconnected. (There is a short in the ECM or between its main bus lines.) B

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  5

  5. CHECK FOR SHORT IN CAN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR) 
    1. Disconnect the D72 CAN main bus line connector.
      GTY549312Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 1 CAN Junction Connector)
      *b to No. 2 CAN Junction Connector
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    2. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *1 DLC3

    Result: 

    NG 

    REPLACE NO. 1 CAN JUNCTION CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK FOR SHORT IN CAN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR) 
    1. Reconnect the D72 CAN main bus line connector.
    2. Disconnect the D78 CAN main bus line connector.
      GTY591126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 2 CAN Junction Connector)
      *b to No. 1 CAN Junction Connector
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    3. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *1 DLC3

    Result: 

    OK 

    REPLACE NO. 2 CAN JUNCTION CONNECTOR 

    Result: 

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR) 

  7. CHECK FOR SHORT IN CAN BUS LINES (ECU, SENSOR) 
    1. Reconnect the connector for the short-circuited branch line to the CAN junction connector (the connector that caused the bus line resistance to become normal (between 54 and 69 Ω) when it was disconnected).
    2. Disconnect the connector that includes the DLC3 connected CAN lines (such as CANH and CANL) from the ECU (or sensor) to which the short-circuited branch line is connected (Refer to TERMINALS OF ECU [10/2015 - ] ).
    3. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      TEXT IN ILLUSTRATION

      *1 DLC3

      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).

    Result: 

    OK 

    REPLACE CORRESPONDING ECU OR SENSOR 

    Result: 

    NG 

    REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BRANCH LINES OR CONNECTOR 

  8. CHECK FOR SHORT IN CAN BUS LINES (COMBINATION METER ASSEMBLY) 
    1. Reconnect the D73 combination meter assembly main bus line connector.
    2. Disconnect the D9 combination meter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *1 DLC3

      HINT: 

      If the resistance becomes normal (between 108 to 132 Ω) when the connector is disconnected, there may be a short in the combination meter assembly.

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY 

    (Refer to REMOVAL [10/2014 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINES (COMBINATION METER ASSEMBLY MAIN LINES) 

  9. CHECK FOR SHORT IN CAN BUS LINES (ECM) 
    1. Reconnect the D81 ECM main bus line connector.
    2. Disconnect the A18 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY577703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      D28-6 (CANH) - D28-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 1 MΩ or higher
      TEXT IN ILLUSTRATION

      *1 DLC3

      HINT: 

      • Measure the resistance with the D73 combination meter assembly main bus line connector disconnected.
      • If the resistance changes to 1 MΩ or more when the connector is disconnected, there may be a short in the ECM.

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [10/2014 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINES (ECM MAIN LINES) 

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