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DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0129: Lost Communication with Brake System Control Module; DTC U0293: Lost Communication with HV ECU [07/2015 - ]: Procedure

  1. RECONFIRM DTC OUTPUT 
    1. Reconfirm DTCs.

      HINT: 

      If the hybrid vehicle control ECU assembly outputs only DTC U0129, troubleshoot DTC U0129 and check the branch circuit of sub bus 15.

      Result

      Result Proceed to
      The hybrid vehicle control ECU assembly outputs DTC U0129 and other DTCs.
      (Techstream display: Hybrid Control)      		 A
      The hybrid vehicle control ECU assembly outputs only DTC U0129.
      (Techstream display: Hybrid Control)      		 B

    Result:  B

    B 

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC 

    Refer to DTC U0129: Lost Communication with Brake System Control Module [07/2015 - ] 

    Result:  A

    A 

    See step  2

  2. CHECK SUB BUS 15 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Measure the resistance according to the value(s) in the table below.
      GTY672077Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H2-31 (CA3P) - H2-30 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω Below 54 Ω: Short circuit between bus lines
      70 Ω or higher: Open circuit in main bus lines
      H2-31 (CA3P) - H2-4 (E12) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      H2-30 (CA3N) - H2-4 (E12) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANL ground short
      H2-31 (CA3P) - H2-3 (BATT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      H2-30 (CA3N) - H2-3 (BATT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANL +B short
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Hybrid Vehicle Control ECU Assembly)

      HINT: 

      • When the values are as specified, clear and recheck for DTCs. When no DTCs are output, check for malfunctions such as damage or improper connection of the relevant connectors.
      • If DTCs are output although the bus circuit is normal and DTCs were cleared, replace the hybrid vehicle control ECU assembly.

      Result

      Result Proceed to
      OK A
      NG (Open circuit in CAN main bus lines) B
      NG (Short circuit between bus lines) C
      • NG (Ground short)
      • NG (+B short)
      		 D

    Result:  A

    A 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY 

    Refer to REMOVAL [07/2015 - ]

    Result:  C

    C 

    See step  6

    Result:  D

    D 

    See step  10

    Result:  B

    B 

    See step  3

  3. CHECK FOR OPEN IN SUB BUS 15 MAIN LINES (HYBRID VEHICLE CONTROL ECU ASSEMBLY) 
    1. Disconnect the H2 hybrid vehicle control ECU assembly connector.
      GTY611805Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H2-31 (CA3P) - H2-30 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)

    Result:  OK

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    See step  4

  4. CHECK FOR OPEN IN SUB BUS 15 MAIN LINES (CAN NO. 1 J/C) 
    1. Reconnect the H2 hybrid vehicle control ECU assembly connector.
    2. Disconnect the A62 CAN No. 1 junction connector.
      GTY657176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      A62-2 (CANH) - A62-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω ECM
      A62-3 (CANH) - A62-6 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Hybrid vehicle control ECU assembly
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to CAN No. 1 Junction Connector)
      *b to ECM
      *c to Hybrid Vehicle Control ECU Assembly

      Result

      Result Proceed to
      OK A
      NG (Open circuit in hybrid vehicle control ECU assembly CAN main bus line) B
      NG (Open circuit in ECM CAN main bus line) C

    Result:  A

    A 

    REPLACE CAN NO. 1 JUNCTION CONNECTOR 

    Result:  B

    B 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - CAN NO. 1 J/C) 

    Result:  C

    C 

    See step  5

  5. CHECK FOR OPEN IN SUB BUS 15 MAIN LINES (ECM - CAN NO. 1 J/C) 
    1. Reconnect the A62 CAN No. 1 junction connector.
    2. Disconnect the A22 ECM connector.
      GTY641616Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A22-12 (CANP) - A22-25 (CANN) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)

    Result:  OK

    OK 

    REPLACE ECM 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (ECM - CAN NO. 1 J/C) 

  6. CHECK FOR SHORT IN SUB BUS 15 LINES (HYBRID VEHICLE CONTROL ECU ASSEMBLY) 
    1. Disconnect the H2 hybrid vehicle control ECU assembly connector.
      GTY611805Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H2-31 (CA3P) - H2-30 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)

    Result:  OK

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    See step  7

  7. CHECK FOR SHORT IN SUB BUS 15 LINES (CAN NO. 1 J/C) 
    1. Reconnect the H2 hybrid vehicle control ECU assembly connector.
    2. Disconnect the A62 CAN No. 1 junction connector.
      GTY623000Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      A62-1 (CANH) - A62-4 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Brake booster with master cylinder assembly (skid control ECU)
      A62-2 (CANH) - A62-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω ECM
      A62-3 (CANH) - A62-6 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Hybrid vehicle control ECU assembly
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to CAN No. 1 Junction Connector)
      *b to Brake Booster with Master Cylinder Assembly (Skid Control ECU)
      *c to ECM
      *d to Hybrid Vehicle Control ECU Assembly

      Result

      Result Proceed to
      OK A
      NG (Short circuit between bus lines in hybrid vehicle control ECU assembly CAN main bus line) B
      NG (Short circuit between bus lines in ECM CAN main bus line) C
      NG (Short circuit between bus lines in brake booster with master cylinder assembly (skid control ECU) CAN branch line) D

    Result:  A

    A 

    REPLACE CAN NO. 1 JUNCTION CONNECTOR 

    Result:  B

    B 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - CAN NO. 1 J/C) 

    Result:  D

    D 

    See step  9

    Result:  C

    C 

    See step  8

  8. CHECK FOR SHORT IN SUB BUS 15 LINES (ECM - CAN NO. 1 J/C) 
    1. Reconnect the A62 CAN No. 1 junction connector.
    2. Disconnect the A22 ECM connector.
      GTY641616Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A22-12 (CANP) - A22-25 (CANN) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)

    Result:  OK

    OK 

    REPLACE ECM 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (ECM - CAN NO. 1 J/C) 

  9. CHECK FOR SHORT IN SUB BUS 15 LINES (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - CAN NO. 1 J/C) 
    1. Reconnect the A62 CAN No. 1 junction connector.
    2. Disconnect the A24 brake booster with master cylinder assembly (skid control ECU) connector.
      GTY620439Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A24-35 (CA2H) - A24-34 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Brake Booster with Master Cylinder Assembly (Skid Control ECU))

    Result:  OK

    OK 

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) 

  10. CHECK FOR SHORT IN SUB BUS 15 LINE (CAN NO. 1 J/C) 
    1. Disconnect the A62 CAN No. 1 junction connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY648349Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition Purpose Connected to
      A62-1 (CANH) - H29-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Inspection for CANH ground short Brake booster with master cylinder assembly (skid control ECU)
      A62-4 (CANL) - H29-4 (CG) Inspection for CANL ground short
      A62-2 (CANH) - H29-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Inspection for CANH ground short ECM
      A62-5 (CANL) - H29-4 (CG) Inspection for CANL ground short
      A62-3 (CANH) - H29-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Inspection for CANH ground short Hybrid vehicle control ECU assembly
      A62-6 (CANL) - H29-4 (CG) Inspection for CANL ground short
      A62-1 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Inspection for CANH +B short Brake booster with master cylinder assembly (skid control ECU)
      A62-4 (CANL) - H29-16 (BAT) Inspection for CANL +B short
      A62-2 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Inspection for CANH +B short ECM
      A62-5 (CANL) - H29-16 (BAT) Inspection for CANL +B short
      A62-3 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Inspection for CANH +B short Hybrid vehicle control ECU assembly
      A62-6 (CANL) - H29-16 (BAT) Inspection for CANL +B short
      TEXT IN ILLUSTRATION

      *1 DLC3 - -
      *a Front view of wire harness connector
      (to CAN No. 1 Junction Connector)      		 *b to Brake Booster with Master Cylinder Assembly (Skid Control ECU)
      *c to ECM *d to Hybrid Vehicle Control ECU Assembly

      HINT: 

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 15 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 15 inspection.

      Result

      Result Proceed to
      OK A
      • NG (Ground short in hybrid vehicle control ECU assembly CAN main bus line)
      • NG (+B short in hybrid vehicle control ECU assembly CAN main bus line)
      		 B
      • NG (Ground short in ECM CAN main bus line)
      • NG (+B short in ECM CAN main bus line)
      		 C
      • NG (Ground short in brake booster with master cylinder assembly (skid control ECU) CAN branch line)
      • NG (+B short in brake booster with master cylinder assembly (skid control ECU) CAN branch line)
      		 D

    Result:  A

    A 

    REPLACE CAN NO. 1 JUNCTION CONNECTOR 

    Result:  C

    C 

    See step  12

    Result:  D

    D 

    See step  13

    Result:  B

    B 

    See step  11

  11. CHECK FOR SHORT IN SUB BUS 15 LINE (HYBRID VEHICLE CONTROL ECU ASSEMBLY - CAN NO. 1 J/C) 
    1. Disconnect the H2 hybrid vehicle control ECU assembly connector.
      GTY684073Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Purpose Specified Condition
      H2-31 (CA3P) - H2-4 (E12) Cable disconnected from negative (-) auxiliary battery terminal Inspection for CANH ground short 200 Ω or higher
      H2-30 (CA3N) - H2-4 (E12) Inspection for CANL ground short
      H2-31 (CA3P) - H2-3 (BATT) Cable disconnected from negative (-) auxiliary battery terminal Inspection for CANH +B short 6 kΩ or higher
      H2-30 (CA3N) - H2-3 (BATT) Inspection for CANL +B short

      HINT: 

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 15 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 15 inspection.
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Hybrid Vehicle Control ECU Assembly)

    Result:  OK

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - CAN NO. 1 J/C) 

  12. CHECK FOR SHORT IN SUB BUS 15 LINE (ECM - CAN NO. 1 J/C) 
    1. Disconnect the A22 and D24 ECM connectors.
      GTY639857Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Purpose Specified Condition
      A22-12 (CANP) - D24-16 (E1) Cable disconnected from negative (-) auxiliary battery terminal Inspection for CANH ground short 200 Ω or higher
      A22-25 (CANN) - D24-16 (E1) Inspection for CANL ground short
      A22-12 (CANP) - A22-1 (BATT) Cable disconnected from negative (-) auxiliary battery terminal Inspection for CANH +B short 6 kΩ or higher
      A22-25 (CANN) - A22-1 (BATT) Inspection for CANL +B short

      HINT: 

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 15 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 15 inspection.
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)

    Result:  OK

    OK 

    REPLACE ECM 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (ECM - CAN NO. 1 J/C) 

  13. CHECK FOR SHORT IN SUB BUS 15 LINE (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - CAN NO. 1 J/C) 
    1. Disconnect the A24 brake booster with master cylinder assembly (skid control ECU) connector.
      GTY621568Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Purpose Specified Condition
      A24-35 (CA2H) - A24-28 (GND) Cable disconnected from negative (-) auxiliary battery terminal Inspection for CANH ground short 200 Ω or higher
      A24-34 (CA2L) - A24-28 (GND) Inspection for CANL ground short
      A24-35 (CA2H) - A24-15 (BS) Cable disconnected from negative (-) auxiliary battery terminal Inspection for CANH +B short 6 kΩ or higher
      A24-34 (CA2L) - A24-15 (BS) Inspection for CANL +B short

      HINT: 

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 15 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 15 inspection.
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Brake Booster with Master Cylinder Assembly (Skid Control ECU))

    Result:  OK

    OK 

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) 

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