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DTC U1002: Lost Communication with Gateway Module (Power Management1): Procedure

  1. CHECK V2 BUS LINES 
    1. Turn the power switch off.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 1: Identifying H3 Connector Terminals
      GTY357186Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition Result
      H3-34 (CA2H) - H3-35 (CA2L) Power switch off 54 to 69 Ω Below 54 Ω:
      Short circuit between bus lines
      70 Ω or higher:
      Open circuit in a main bus line
      H3-34 (CA2H) - H3-6 (E1) Power switch off 200 Ω or higher Below 200 Ω:
      CANH ground short
      H3-35 (CA2L) - H3-6 (E1) Power switch off 200 Ω or higher Below 200 Ω:
      CANL ground short
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Power Management Control ECU)
    3. Disconnect the cable from the negative (-) battery terminal.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H3-34 (CA2H) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short
      H3-35 (CA2L) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANL +B short

      Result

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

    B → See step   3 

    C → See step   5 

    D → See step   9 

    A: Go to next step 

  2. CHECK DTC OUTPUT 
    1. Clear the DTCs.
    2. Turn the power switch off.
    3. Turn the power switch on (IG) and recheck for DTCs.

      Result

      Result Proceed to
      U1002 is output from power management control ECU
      (Techstream display: PM1 Gateway)      		 A
      Other DTC is output B

    B → GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC 

    A → See step   13 

  3. CHECK FOR OPEN IN V2 BUS MAIN LINES (POWER MANAGEMENT CONTROL ECU MAIN WIRE) 
    1. Disconnect the power management control ECU connector.
      Fig 2: Identifying H3 Connector Terminals
      GTY352215Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      H3-34 (CA2H) - H3-35 (CA2L) Power switch off 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

    NG → See step   4 

    OK → See step   13 

  4. CHECK FOR OPEN IN V2 BUS MAIN LINES (CAN NO. 4 J/C - POWER MANAGEMENT CONTROL ECU) 
    1. Reconnect the power management control ECU connector.
    2. Disconnect the power management control ECU main line connector from the CAN No. 4 junction connector.
      Fig 3: Identifying H106 Connector Terminals
      GTY354600Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition Connected to
      H106-1 (CANH) - H106-2 (CANL) Power switch off 108 to 132 Ω Power management control ECU
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to CAN No. 4 Junction Connector)
      *b to Power Management Control ECU

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

    OK → REPLACE CAN NO. 4 JUNCTION CONNECTOR 

  5. CHECK FOR SHORT IN V2 BUS LINES (POWER MANAGEMENT CONTROL ECU) 
    1. Disconnect the power management control ECU connector.
      Fig 4: Identifying H3 Connector Terminals
      GTY352215Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      H3-34 (CA2H) - H3-35 (CA2L) Power switch off 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

    NG → See step   6 

    OK → See step   13 

  6. CHECK FOR SHORT IN V2 BUS LINES (CAN NO. 4 J/C - POWER MANAGEMENT CONTROL ECU) 
    1. Reconnect the power management control ECU connector.
    2. Disconnect the power management control ECU main line connector from the CAN No. 4 junction connector.
      Fig 5: Identifying H106 Connector Terminals
      GTY354600Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition Connected to
      H106-1 (CANH) - H106-2 (CANL) Power switch off 108 to 132 Ω Power management control ECU
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to CAN No. 4 Junction Connector)
      *b to Power Management Control ECU

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

    OK: Go to next step 

  7. CHECK FOR SHORT IN V2 BUS LINES (CAN NO. 4 J/C) 
    1. Reconnect the power management control ECU main line connector to the CAN No. 4 junction connector.
    2. Connect the probes of an ohmmeter to terminals 34 (CA2H) and 35 (CA2L) of the power management control ECU.
      Fig 6: Identifying H3 Connector Terminals
      GTY357187Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connector
      (Power Management Control ECU)
    3. While observing the resistance value shown on the ohmmeter, disconnect branch line connectors (except H106) from the CAN No. 4 junction connector until the resistance becomes normal (between 54 and 69 Ω).
      Fig 7: CAN No. 4 Junction Connector View
      GTY398599Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 CAN No. 4 Junction Connector - -
      *a Junction Connector B Side *b Junction Connector A Side
      *c Earth Terminal *d Front view of wire harness connector
      (to CAN No. 4 Junction Connector)
      JUNCTION CONNECTOR A SIDE

      Terminal No. (Symbol) Wiring Color Connected to
      H111-1 (GND) W-B Body ground
      H106-1 (CANH) R Power management control ECU
      H106-2 (CANL) B
      H107-1 (CANH) G Clearance warning ECU assembly
      H107-2 (CANL) B
      H108-1 (CANH) L Driving support ECU assembly
      H108-2 (CANL) B
      H109-1 (CANH) Y Seat belt control ECU
      H109-2 (CANL) B

      HINT: 

      • The connectors connected to the CAN junction connector can be distinguished by the colors of the bus line.
      • Reconnecting the connectors to non-specified positions on the CAN junction connector does not affect system operation.

        Result

        Result Proceed to
        The resistance is still below 54 Ω when all the specified connectors are disconnected.
        (There is no short in the branch lines.)        		 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 lines.)        		 B

    B → See step   8 

    A → REPLACE CAN NO. 4 JUNCTION CONNECTOR 

  8. CHECK FOR SHORT IN V2 BUS LINES (ECUS) 
    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 terminals CANH and CANL from the ECU to which the short-circuited branch line is connected.
    3. Measure the resistance according to the value(s) in the table below.
      Fig 8: Identifying H3 Connector Terminals
      GTY357187Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      H3-34 (CA2H) - H3-35 (CA2L) Power switch off 54 to 69 Ω
      TEXT IN ILLUSTRATION

      *a Component with harness connector
      (Power Management Control ECU)

      HINT: 

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

    NG → REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BRANCH LINE OR CONNECTOR 

    OK → REPLACE CORRESPONDING ECU OR SENSOR 

  9. CHECK FOR SHORT IN V2 BUS LINE (POWER MANAGEMENT CONTROL ECU) 
    1. Disconnect the power management control ECU connector.
      Fig 9: Identifying E1 Connector Terminals
      GTY352214Courtesy 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 Purpose
      H3-34 (CA2H) - H3-6 (E1) Power switch off 200 Ω or higher Inspection for CANH ground short
      H3-35 (CA2L) - H3-6 (E1) Power switch off 200 Ω or higher Inspection for CANL ground short
      H3-34 (CA2H) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANH +B short
      H3-35 (CA2L) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANL +B short
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

      HINT: 

      It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check V2 Bus Line inspection.

      Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check V2 Bus Line inspection.

    NG → See step   10 

    OK → See step   13 

  10. CHECK FOR SHORT IN V2 BUS LINE (CAN NO. 4 J/C - POWER MANAGEMENT CONTROL ECU) 
    1. Disconnect the power management control ECU main line connector from the CAN No. 4 junction connector.
      Fig 10: Identifying H106 Connector Terminals
      GTY354600Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to CAN No. 4 Junction Connector)
      *b to Power Management Control ECU
    2. Measure the resistance according to the value(s) in the table below.
      Fig 11: Identifying E1 Connector Terminals
      GTY352214Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition Purpose
      H3-34 (CA2H) - H3-6 (E1) Power switch off 200 Ω or higher Inspection for CANH ground short
      H3-35 (CA2L) - H3-6 (E1) Power switch off 200 Ω or higher Inspection for CANL ground short
      H3-34 (CA2H) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANH +B short
      H3-35 (CA2L) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher 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 V2 Bus Line inspection.

      Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check V2 Bus Line inspection.

      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

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

    OK: Go to next step 

  11. CHECK FOR SHORT IN V2 BUS LINE (CAN NO. 4 J/C) 
    1. Reconnect the power management control ECU main line connector to the CAN No. 4 junction connector.
    2. Connect the probes of an ohmmeter to terminals CANH or CANL and GND or +B (AM22) of the power management control ECU.
      Fig 12: Identifying E1 Connector Terminals
      GTY352214Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

      HINT: 

      It is only necessary to perform the inspection for the result (short circuit) that was obtained in the Check V2 Bus Line inspection.

    3. While observing the resistance value shown on the ohmmeter, disconnect branch line connectors (except H106) from the CAN No. 4 junction connector until the resistance becomes normal (6 kΩ or higher (for +B short) or 200 Ω or higher (for ground short)).
      Fig 13: CAN No. 4 Junction Connector View
      GTY398599Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 CAN No. 4 Junction Connector - -
      *a Junction Connector B Side *b Junction Connector A Side
      *c Earth Terminal *d Front view of wire harness connector
      (to CAN No. 4 Junction Connector)
      JUNCTION CONNECTOR A SIDE

      Terminal No. (Symbol) Wiring Color Connected to
      H111-1 (GND) W-B Body ground
      H106-1 (CANH) R Power management control ECU
      H106-2 (CANL) B
      H107-1 (CANH) G Clearance warning ECU assembly
      H107-2 (CANL) B
      H108-1 (CANH) L Driving support ECU assembly
      H108-2 (CANL) B
      H109-1 (CANH) Y Seat belt control ECU
      H109-2 (CANL) B

      HINT: 

      • The connectors connected to the CAN junction connector can be distinguished by the colors of the bus line.
      • Reconnecting the connectors to non-specified positions on the CAN junction connector does not affect system operation.

        Result

        Result Proceed to
        The resistance between terminals CANH and BAT, or the resistance between terminals CANL and BAT is still below 6 kΩ when all the specified connectors are disconnected from the CAN junction connector.
        (There is no short to +B in the branch lines.)        		 A
        The resistance between terminals CANH and GND, or the resistance between terminals CANL and GND is still below 200 Ω when all the specified connectors are disconnected from the CAN junction connector.
        (There is no short to GND in the branch lines.)
        The resistance between terminals CANH and BAT, or the resistance between terminals CANL and BAT becomes normal (6 kΩ or higher) when a connector is disconnected from the CAN junction connector.
        (There is a short to +B in one of the areas related to one or more of the disconnected branch lines.)        		 B
        The resistance between terminals CANH and GND, or the resistance between terminals CANL and GND becomes normal (200 Ω or higher) when a connector is disconnected from the CAN junction connector.
        There is a short to GND in one of the areas related to one or more of the disconnected branch lines.)

    B → See step   12 

    A → REPLACE CAN NO. 4 JUNCTION CONNECTOR 

  12. CHECK FOR SHORT IN V2 BUS LINE (ECUS) 
    1. Reconnect the connector for the bus line that is shorted to +B or GND to the CAN junction connector (the connector that caused the bus line resistance to change to 6 kΩ or higher (for +B short) or 200 Ω or higher (for ground short) when it was disconnected).
    2. Disconnect the connector that includes terminals CANH and CANL from the ECU to which the bus line shorted to +B or GND is connected.
    3. Measure the resistance according to the value(s) in the table below.
      Fig 14: Identifying E1 Connector Terminals
      GTY352214Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition Purpose
      H3-34 (CA2H) - H3-6 (E1) Power switch off 200 Ω or higher Inspection for CANH ground short
      H3-35 (CA2L) - H3-6 (E1) Power switch off 200 Ω or higher Inspection for CANL ground short
      H3-34 (CA2H) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Inspection for CANH +B short
      H3-35 (CA2L) - H3-1 (AM22) Cable disconnected from negative (-) battery terminal 6 kΩ or higher 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 V2 Bus Line inspection.

      Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check V2 Bus Line inspection.

      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

    NG → REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BRANCH LINE OR CONNECTOR 

    OK → REPLACE CORRESPONDING ECU OR SENSOR 

  13. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL [08/2012 - ] 
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