CAN COMMUNICATION SYSTEM, Diagnostic DTC:U0100, U0129, U0293

DTC Code DTC Name
U0100 Lost Communication with ECM / PCM "A"
U0129 Lost Communication with Brake System Control Module
U0293 Lost Communication with HV ECU

DESCRIPTION


DTC No. DTC Detection Condition Trouble Area
U0100 The power management control ECU does not receive data from the ECM.

  • Open or short in power management main bus wire or connector

  • Open or short in power management bus branch wire or connector

  • Power source circuit of power management control ECU

  • Power management control ECU

  • Power source circuit of ECM

  • ECM

  • Open or short in CAN No. 4 junction connector
U0129 The power management control ECU does not receive data from the brake booster with master cylinder (skid control ECU).

  • Open or short in power management main bus wire or connector

  • Open or short in power management bus branch wire or connector

  • Power source circuit of power management control ECU

  • Power management control ECU

  • Power source circuit of brake booster with master cylinder (skid control ECU)

  • Brake booster with master cylinder (skid control ECU)

  • Open or short in CAN No. 4 junction connector
U0293

  • The ECM does not receive data from the power management control ECU.

  • The brake booster with master cylinder (skid control ECU) does not receive data from the power management control ECU.

  • Open or short in power management main bus wire or connector

  • Open or short in power management bus branch wire or connector

  • Power source circuit of ECM

  • ECM

  • Power source circuit of power management control ECU

  • Power management control ECU

  • Power source circuit of brake booster with master cylinder (skid control ECU)

  • Brake booster with master cylinder (skid control ECU)

  • Open or short in CAN No. 4 junction connector

Tech Tips

This diagnosis procedure is for when DTC U0100, U0129 and U0293 are output at the same time.

WIRING DIAGRAM

A0043MEE06

INSPECTION PROCEDURE

Note


  • Turn the power switch off before measuring the resistances between CAN main bus wires and between CAN main bus branch wires.

  • Turn the power switch off before inspecting CAN bus wires for a ground short.

  • After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power 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.

Tech Tips


  • Operating the power switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE


  1. RECONFIRM DTC OUTPUT


    1. Check if Hybrid Control of the power management control ECU outputs only DTC U0129.

      Tech Tips

      If the power management control ECU outputs only DTC U0129, troubleshoot DTC U0129 and check the branch circuit of power management bus.

      Result
      Result Proceed to

      The power management control ECU outputs DTC U0129 and other DTCs.

      (GTS display: Hybrid Control)

      		 A

      The power management control ECU outputs only DTC U0129.

      (GTS display: Hybrid Control)

      		 B

    B

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC

    A

  2. CHECK POWER MANAGEMENT BUS


    1. Disconnect the cable from the negative (-) auxiliary battery terminal.

    2. A0040QKE11
      Text in Illustration
      *a

      Component with harness connected

      (Power Management Control ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition Result
      L6-31 (CA3P) - L6-30 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω Below 54 Ω: Short circuit between bus wires
      70 Ω or higher: Open circuit in a main bus wire
      L6-31 (CA3P) - L6-4 (E12) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      L6-30 (CA3N) - L6-4 (E12) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANL ground short

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

      Standard Resistance
      Tester Connection Condition Specified Condition Result
      L6-31 (CA3P) - L6-7 (AM21) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      L6-30 (CA3N) - L6-7 (AM21) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANL +B short

      Tech Tips


      • 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 power management control ECU.

      Result
      Result Proceed to
      OK A
      NG (Open circuit in main bus wire) B
      NG (Short circuit between bus wires) C

      • NG (Ground short)

      • NG (+B short)

      		 D

    B

    CHECK FOR OPEN IN POWER MANAGEMENT MAIN BUS WIRES (POWER MANAGEMENT CONTROL ECU) Click here

    C

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (POWER MANAGEMENT CONTROL ECU) Click here

    D

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 4 J/C) Click here

    A

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  3. CHECK FOR OPEN IN POWER MANAGEMENT MAIN BUS WIRES (POWER MANAGEMENT CONTROL ECU)


    1. A0042Q7E71
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the L6 power management control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L6-31 (CA3P) - L6-30 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG

    CHECK FOR OPEN IN POWER MANAGEMENT MAIN BUS WIRES (CAN NO. 4 J/C) Click here

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  4. CHECK FOR OPEN IN POWER MANAGEMENT MAIN BUS WIRES (CAN NO. 4 J/C)


    1. Reconnect the L6 power management control ECU connector.

    2. A00422OE12
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 4 Junction Connector)
      *b to Power Management Control ECU
      *c to ECM

      Disconnect the L86 CAN No. 4 junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L86-12 (CANH) - L86-1 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Power management control ECU
      L86-15 (CANH) - L86-4 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω ECM
      Result
      Result Proceed to
      OK A
      NG (Open circuit in power management control ECU CAN main bus wire) B
      NG (Open circuit in ECM CAN main bus wire) C

    B

    REPAIR OR REPLACE CAN MAIN BUS WIRE OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 J/C)

    C

    CHECK FOR OPEN IN POWER MANAGEMENT MAIN BUS WIRES (ECM - CAN NO. 4 J/C) Click here

    A

    REPLACE CAN NO. 4 JUNCTION CONNECTOR

  5. CHECK FOR OPEN IN POWER MANAGEMENT MAIN BUS WIRES (ECM - CAN NO. 4 J/C)


    1. Reconnect the L86 CAN No. 4 junction connector.

    2. A00406ME73
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the A56 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A56-12 (CANP) - A56-4 (CANN) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG

    REPAIR OR REPLACE CAN MAIN BUS WIRE OR CONNECTOR (ECM - CAN NO. 4 J/C)

    OK

    REPLACE ECM Click here

  6. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (POWER MANAGEMENT CONTROL ECU)


    1. A0042Q7E71
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the L6 power management control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L6-31 (CA3P) - L6-30 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (CAN NO. 4 J/C) Click here

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  7. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (CAN NO. 4 J/C)


    1. Reconnect the L6 power management control ECU connector.

    2. A00422OE13
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 4 Junction Connector)
      *b to Power Management Control ECU
      *c to Brake Booster with Master Cylinder (Skid Control ECU)
      *d to ECM

      Disconnect the L86 CAN No. 4 junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L86-12 (CANH) - L86-1 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Power management control ECU
      L86-14 (CANH) - L86-3 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Brake booster with master cylinder (Skid control ECU)
      L86-15 (CANH) - L86-4 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω ECM
      Result
      Result Proceed to
      OK A
      NG (Short circuit between bus wires in power management control ECU CAN main bus wire) B
      NG (Short circuit between bus lines in ECM CAN main bus wire) C
      NG (Short circuit between bus lines in brake booster with master cylinder assembly (skid control ECU) CAN main bus branch wire) D

    B

    REPAIR OR REPLACE CAN MAIN BUS WIRE OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 J/C)

    C

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (ECM - CAN NO. 4 J/C) Click here

    D

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (BRAKE BOOSTER WITH MASTER CYLINDER - CAN NO. 4 J/C) Click here

    A

    REPLACE CAN NO. 4 JUNCTION CONNECTOR

  8. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (ECM - CAN NO. 4 J/C)


    1. Reconnect the L86 CAN No. 4 junction connector.

    2. A00406ME73
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the A56 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A56-12 (CANP) - A56-4 (CANN) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG

    REPAIR OR REPLACE CAN MAIN BUS WIRE OR CONNECTOR (ECM - CAN NO. 4 J/C)

    OK

    REPLACE ECM Click here

  9. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRES (BRAKE BOOSTER WITH MASTER CYLINDER - CAN NO. 4 J/C)


    1. Reconnect the L86 CAN No. 4 junction connector.

    2. A0044BAE82
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Brake Booster with Master Cylinder (Skid Control ECU))

      Disconnect the A57 brake booster with master cylinder (skid control ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A57-35 (CA2H) - A57-34 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (SKID CONTROL ECU) Click here

    C

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER - CAN NO. 4 J/C)

    A

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (SKID CONTROL ECU) Click here

  10. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (CAN NO. 4 J/C)


    1. Disconnect the L86 CAN No. 4 junction connector.

      A0040DRE03

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

      Standard Resistance
      Tester Connection Condition Specified Condition Purpose Connected to
      L86-12 (CANH) - L55-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Inspection for CANH ground short Power management control ECU
      L86-1 (CANL) - L55-4 (CG) Inspection for CANL ground short
      L86-14 (CANH) - L55-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Inspection for CANH ground short Brake booster with master cylinder (skid control ECU)
      L86-3 (CANL) - L55-4 (CG) Inspection for CANL ground short
      L86-15 (CANH) - L55-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Inspection for CANH ground short ECM
      L86-4 (CANL) - L55-4 (CG) Inspection for CANL ground short
      L86-12 (CANH) - L55-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Inspection for CANH +B short Power management control ECU
      L86-1 (CANL) - L55-16 (BAT) Inspection for CANL +B short
      L86-14 (CANH) - L55-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Inspection for CANH +B short Brake booster with master cylinder (skid control ECU)
      L86-3 (CANL) - L55-16 (BAT) Inspection for CANL +B short
      L86-15 (CANH) - L55-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Inspection for CANH +B short ECM
      L86-4 (CANL) - L55-16 (BAT) Inspection for CANL +B short
      Text in Illustration
      *1 DLC3 - -
      *a

      Front view of wire harness connector

      (to CAN No. 4 Junction Connector)

      		 *b to Power Management Control ECU
      *c to Brake Booster with Master Cylinder (Skid Control ECU) *d to ECM

      Tech Tips


      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Power Management Bus inspection.

        Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Power Management Bus inspection.

      • If the resistance changes to normal when the connector is disconnected from the ECU, there may be a short in the ECU.

      Result
      Result Proceed to
      OK A

      • NG (Ground short in power management control ECU CAN main bus wire)

      • NG (+B short in power management control ECU CAN main bus wire)

      		 B

      • NG (Ground short in ECM CAN main bus wire)

      • NG (+B short in ECM CAN main bus wire)

      		 C

      • NG (Ground short in brake booster with master cylinder (skid control ECU) CAN main bus branch wire)

      • NG (+B short in brake booster with master cylinder (skid control ECU) CAN main bus branch wire)

      		 D

    B

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 J/C) Click here

    C

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (ECM - CAN NO. 4 J/C) Click here

    D

    CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (BRAKE BOOSTER WITH MASTER CYLINDER - CAN NO. 4 J/C) Click here

    A

    REPLACE CAN NO. 4 JUNCTION CONNECTOR

  11. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 J/C)


    1. A0042Q7E72
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the L6 power management control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Purpose
      L6-31 (CA3P) - L6-4 (E12) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      L6-30 (CA3N) - L6-4 (E12) Below 200 Ω: CANL ground short
      L6-31 (CA3P) - L6-7 (AM21) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      L6-30 (CA3N) - L6-7 (AM21) Below 6 kΩ: CANL +B short

      Tech Tips


      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check power management bus inspection.

      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check power management bus inspection.


    NG

    REPAIR OR REPLACE CAN MAIN BUS WIRE OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 J/C)

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  12. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (ECM - CAN NO. 4 J/C)


    1. A004032E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the A56 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Purpose
      A56-12 (CANP) - D28-104 (E1) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      A56-4 (CANN) - D28-104 (E1) Below 200 Ω: CANL ground short
      A56-12 (CANP) - A56-20 (BATT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      A56-4 (CANN) - A56-20 (BATT) Below 6 kΩ: CANL +B short

      Tech Tips


      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Power Management Bus inspection.

        Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Power Management Bus inspection.

      • If the resistance changes to normal when the connector is disconnected from the ECU, there may be a short in the ECU.


    NG

    REPAIR OR REPLACE CAN MAIN BUS WIRE OR CONNECTOR (ECM - CAN NO. 4 J/C)

    OK

    REPLACE ECM Click here

  13. CHECK FOR SHORT IN POWER MANAGEMENT BUS WIRE (BRAKE BOOSTER WITH MASTER CYLINDER - CAN NO. 4 J/C)


    1. A0044BAE83
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Brake Booster with Master Cylinder (Skid Control ECU))

      Disconnect the A57 brake booster with master cylinder (skid control ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Purpose
      A57-35 (CA2H) - A57-28 (GND) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      A57-34 (CA2L) - A57-28 (GND) Below 200 Ω: CANL ground short
      A57-35 (CA2H) - A57-15 (BS) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      A57-34 (CA2L) - A57-15 (BS) Below 6 kΩ: CANL +B short
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

      Tech Tips


      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Power Management Bus inspection.

        Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Power Management Bus inspection.

      • If the resistance changes to normal when the connector is disconnected from the ECU, there may be a short in the ECU.


    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (SKID CONTROL ECU) Click here

    C

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER - CAN NO. 4 J/C)

    A

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (SKID CONTROL ECU) Click here