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DTC U1002: Lost Communication with Gateway Module [11/2017 - 09/2019]: Procedure

  1. CHECK CAN BUS LINE (MALFUNCTION CONFIRMATION) 
    1. Turn the ignition switch off.
    2. Disconnect the cable from the negative (-) battery terminal.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      M8-5 (CA1P) - M8-6 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω Below 54 Ω:
      Short circuit between CAN bus lines
      70 Ω or more:
      Open circuit in a CAN bus line
      M8-5 (CA1P) - M8-1 (SGND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      Ground short
      M8-6 (CA1N) - M8-1 (SGND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      Ground short
      M8-5 (CA1P) - M8-8 (IGB) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      +B short
      M8-6 (CA1N) - M8-8 (IGB) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      +B short
      GTY768967Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Millimeter Wave Radar Sensor Assembly)

      Result

      Result Proceed to
      OK A
      NG (Open circuit in CAN bus line) B
      NG (Short circuit between CAN bus lines) C
      NG (Short to +B or ground) D

    Result: 

    B 

    See step  3

    Result: 

    C 

    See step  6

    Result: 

    D 

    See step  9

    Result: 

    A 

    See step  2

  2. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [11/2017 - ]

    2. Make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [11/2017 - ]

      Result

      Result Proceed to
      DTC U1002 is not output A
      DTC U1002 is output B

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 09/2019] 

    Result: 

    B 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [11/2017 - 09/2019] 

  3. CHECK FOR OPEN IN CAN BUS LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - FORWARD RECOGNITION CAMERA) 
    1. Disconnect the F46 forward recognition camera connector.
    2. Disconnect the M8 millimeter wave radar sensor assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F46-6 (CANH) - M8-5 (CA1P) Cable disconnected from negative (-) battery terminal Below 1 Ω
      F46-12 (CANL) - M8-6 (CA1N) Cable disconnected from negative (-) battery terminal Below 1 Ω
    4. Connect the M8 millimeter wave radar sensor assembly connector.
    5. Connect the F46 forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  4

  4. CHECK FOR OPEN IN CAN BUS LINES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the forward recognition camera connector.
      GTY747074Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F46-6 (CANH) - F46-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [11/2017 - ] 

    Result: 

    NG 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [11/2017 - 09/2019] 

  5. CHECK MILLIMETER WAVE RADAR WIRE 
    1. Disconnect the M8 millimeter wave radar sensor assembly connector.
    2. Disconnect the EP1 millimeter wave radar wire connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      EP1-5 - M8-5 (CA1P) Always Below 1 Ω
      EP1-6 - M8-6 (CA1N) Always Below 1 Ω
    4. Connect the M8 millimeter wave radar assembly connector.
    5. Connect the EP1 millimeter wave radar sensor wire connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE CAN BUS LINE OR CONNECTOR (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - FORWARD RECOGNITION CAMERA) 

    Result: 

    NG 

    REPAIR MILLIMETER WAVE RADAR WIRE. Refer to  REMOVAL [11/2017 - 09/2019] 

  6. CHECK FOR SHORT BETWEEN CAN BUS LINES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the forward recognition camera connector.
      GTY747076Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F46-6 (CANH) - F46-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [11/2017 - ] 

    Result: 

    NG 

    See step  7

  7. CHECK FOR SHORT BETWEEN CAN BUS LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY765434Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      M8-5 (CA1P) - M8-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [11/2017 - 09/2019] 

    Result: 

    NG 

    See step  8

  8. CHECK MILLIMETER WAVE RADAR WIRE 
    1. Disconnect the millimeter wave radar wire connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      EP1-5 - EP1-6 Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      GTY765424Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Millimeter Wave Radar Wire)
    3. Connect the millimeter wave radar sensor wire connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR MILLIMETER WAVE RADAR WIRE. Refer to  REMOVAL [11/2017 - 09/2019] 

    Result: 

    NG 

    REPAIR OR REPLACE CAN BUS LINE OR CONNECTOR (MILLIMETER WAVE RADAR WIRE - FORWARD RECOGNITION CAMERA) 

  9. CHECK FOR SHORT IN CAN BUS LINE (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the forward recognition camera connector.
      GTY765863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 DLC3 - -
      *a Front view of wire harness connector
      (to Forward Recognition Camera)      		 - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F46-6 (CANH) - D4-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      F46-12 (CANL) - D4-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      F46-6 (CANH) - D4-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      F46-12 (CANL) - D4-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
    3. Connect the forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [11/2017 - ] 

    Result: 

    NG 

    See step  10

  10. CHECK FOR SHORT IN CAN BUS LINE (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY767404Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 DLC3 - -
      *a Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)      		 - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      M8-5 (CA1P) - D4-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      M8-6 (CA1N) - D4-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      M8-5 (CA1P) - D4-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      M8-6 (CA1N) - D4-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
    3. Connect the millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [11/2017 - 09/2019] 

    Result: 

    NG 

    See step  11

  11. CHECK FOR SHORT IN CAN BUS LINE (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the millimeter wave radar wire connector.
      GTY767406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 DLC3 - -
      *a Front view of wire harness connector
      (to Millimeter Wave Radar Wire)      		 - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      EP1-5 - D4-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      EP1-6 - D4-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      EP1-5 - D4-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      EP1-6 - D4-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
    3. Connect the millimeter wave radar wire connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR MILLIMETER WAVE RADAR WIRE. Refer to  REMOVAL [11/2017 - 09/2019] 

    Result: 

    NG 

    REPAIR OR REPLACE CAN BUS LINE OR CONNECTOR (MILLIMETER WAVE RADAR WIRE - FORWARD RECOGNITION CAMERA) 

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