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DTC U1002: Lost Communication with Gateway Module [08/2016 - ]: 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.
      GTY718483Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Driving Support ECU Assembly)

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      E71-8 (CA1P) - E71-9 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω Below 54 Ω:
      Short circuit between bus lines
      70 Ω or more:
      Open circuit in a main bus line or driving support ECU assembly branch line
      E71-8 (CA1P) - E71-28 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANH ground short
      E71-9 (CA1N) - E71-28 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANH ground short
      E71-8 (CA1P) - E71-7 (B) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short
      E71-9 (CA1N) - E71-7 (B) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short

      Result

      Result Proceed to
      OK A
      NG (Open circuit in main line or Driving support ECU assembly branch line) B
      NG (Short circuit between main lines) C
      NG (Short to +B or ground) D

    Result:  2

    B 

    See step  3

    Result:  3

    C 

    See step  8

    Result:  4

    D 

    See step  12

    Result:  1

    A 

    See step  2

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

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Body Electrical > Pre-Collision 2 > Clear DTCs 

    2. Perform the following procedure.

      HINT: 

      If the following procedure is not performed, the previously output DTC cannot be detected.

      1. Turn the ignition switch to ON and wait 2 seconds or more.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Body Electrical > Pre-Collision 2 > Trouble Codes 

      Result

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

    Result:  1

    A 

    USE SIMULATION METHOD TO CHECK:  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 08/2017]  Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - ] 

    Result:  2

    B 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY:  COMPONENTS [08/2016 - ] 

  3. CHECK FOR OPEN IN CAN BUS BRANCH LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the E71 driving support ECU assembly connector.
      GTY727792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E71-8 (CA1P) - E71-9 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

      HINT: 

      If the resistance is between 108 and 132 Ω, there may be an open in a CAN bus main line. If the value is 132 Ω or more, there may be an open in a CAN bus branch line between the No. 5 CAN junction connector and the driving support ECU or a connector may be disconnected.

    3. Connect the E71 driving support ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    See step  7

    Result:  1

    OK 

    See step  4

  4. CHECK FOR OPEN IN CAN BUS MAIN LINES (NO. 5 CAN JUNCTION CONNECTOR) 
    1. Disconnect the E78 No. 5 CAN junction connector.
      GTY704409Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to No. 5 CAN Junction Connector)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      E78-7 (CANH) - E78-18 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Forward Recognition Camera
      E78-6 (CA1P) - E78-17 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Millimeter Wave Radar Sensor Assembly
    3. Connect the E78 No. 5 CAN junction connector.

      Result

      Result Proceed to
      OK A
      NG (Forward Recognition Camera Main Line) B
      NG (Millimeter Wave Radar Sensor Assembly Main Line) C

    Result:  1

    A 

    REPLACE NO. 5 CAN JUNCTION CONNECTOR 

    Result:  3

    C 

    See step  6

    Result:  2

    B 

    See step  5

  5. CHECK FOR OPEN IN CAN BUS MAIN LINES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the O9 forward recognition camera connector.
      GTY710867Courtesy 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
      O9-6 (CANH) - O9-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the O9 forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE FORWARD RECOGNITION CAMERA:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

  6. CHECK FOR OPEN IN CAN BUS MAIN LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the A50 millimeter wave radar sensor assembly connector.
      GTY722434Courtesy 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
      A50-5 (CA1P) - A50-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the A50 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

  7. CHECK FOR OPEN IN CAN BUS BRANCH LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the E71 driving support ECU assembly connector.
      GTY727792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)
    2. Disconnect the E78 No. 5 CAN junction connector.
      GTY704407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to No. 5 CAN Junction Connector)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E78-5 (CA1P) - E71-8 (CA1P) Cable disconnected from negative (-) battery terminal Below 1 Ω
      E78-16 (CA1N) - E71-9 (CA1N) Cable disconnected from negative (-) battery terminal Below 1 Ω
    4. Connect the E78 No. 5 CAN junction connector.
    5. Connect the E71 driving support ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE NO. 5 CAN JUNCTION CONNECTOR 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS BRANCH WIRE (NO. 5 CAN JUNCTION CONNECTOR - DRIVING SUPPORT ECU ASSEMBLY) 

  8. CHECK FOR SHORT BETWEEN CAN BUS LINES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the O9 forward recognition camera connector.
      GTY710867Courtesy 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
      O9-6 (CANH) - O9-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the O9 forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE FORWARD RECOGNITION CAMERA:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    See step  9

  9. CHECK FOR SHORT BETWEEN CAN BUS LINES (NO. 5 CAN JUNCTION CONNECTOR) 
    1. Disconnect the E78 No. 5 CAN junction connector.
      GTY734852Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to No. 5 CAN junction connector)
      *b to Forward Recognition Camera
      *c to Millimeter Wave Radar Sensor Assembly
      *d to Driving Support ECU Assembly
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      E78-7 (CANH) - E78-18 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Forward Recognition Camera
      E78-6 (CA1P) - E78-17 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Millimeter Wave Radar Sensor Assembly
      E78-5 (CA1P) - E78-16 (CA1N) Cable disconnected from negative (-) battery terminal 200 Ω or higher Driving Support ECU Assembly
    3. Connect the E78 No. 5 CAN junction connector.

      Result

      Result Proceed to
      OK A
      NG (Forward Recognition Camera Main Line) B
      NG (Millimeter Wave Radar Sensor Assembly Main Line) C
      NG (Driving Support ECU Assembly Branch Line) D

    Result:  1

    A 

    REPLACE NO. 5 CAN JUNCTION CONNECTOR 

    Result:  2

    B 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

    Result:  4

    D 

    See step  11

    Result:  3

    C 

    See step  10

  10. CHECK FOR SHORT BETWEEN CAN BUS LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the A50 millimeter wave radar sensor assembly connector.
      GTY722434Courtesy 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
      A50-5 (CA1P) - A50-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
    3. Connect the A50 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

  11. CHECK FOR SHORT BETWEEN CAN BUS LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the E71 driving support ECU assembly connector.
      GTY727792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E71-8 (CA1P) - E71-9 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
    3. Connect the E71 driving support ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS BRANCH LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - DRIVING SUPPORT ECU ASSEMBLY) 

  12. CHECK FOR SHORT IN CAN BUS LINE (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the O9 forward recognition camera connector.
      GTY723969Courtesy 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
      O9-6 (CANH) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      O9-12 (CANL) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      O9-6 (CANH) - E13-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      O9-12 (CANL) - E13-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
    3. Connect the O9 forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE FORWARD RECOGNITION CAMERA:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    See step  13

  13. CHECK FOR SHORT IN CAN BUS LINE (NO. 5 CAN JUNCTION CONNECTOR) 
    1. Disconnect the E78 No. 5 CAN junction connector.
      GTY733528Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 DLC3 - -
      *a Front view of wire harness connector
      (to No. 5 CAN junction connector)      		 *b to Forward Recognition Camera
      *c to Millimeter Wave Radar Sensor Assembly *d to Driving Support ECU Assembly
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      E78-7 (CANH) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Forward Recognition Camera
      E78-18 (CANL) - E13-4 (CG)
      E78-7 (CANH) - E13-16 (BAT) 6 kΩ or higher
      E78-18 (CANL) - E13-16 (BAT)
      E78-6 (CA1P) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Millimeter Wave Radar Sensor Assembly
      E78-17 (CA1N) - E13-4 (CG)
      E78-6 (CA1P) - E13-16 (BAT) 6 kΩ or higher
      E78-17 (CA1N) - E13-16 (BAT)
      E78-5 (CA1P) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Driving Support ECU Assembly
      E78-16 (CA1N) - E13-4 (CG)
      E78-5 (CA1P) - E13-16 (BAT) 6 kΩ or higher
      E78-16 (CA1N) - E13-16 (BAT)
    3. Connect the E78 No. 5 CAN junction connector.

      Result

      Result Proceed to
      OK A
      NG (Forward Recognition Camera Main Line) B
      NG (Millimeter Wave Radar Sensor Assembly Main Line) C
      NG (Driving Support ECU Assembly Branch Line) D

    Result:  1

    A 

    REPLACE NO. 5 CAN JUNCTION CONNECTOR 

    Result:  2

    B 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

    Result:  4

    D 

    See step  15

    Result:  3

    C 

    See step  14

  14. CHECK FOR SHORT IN CAN BUS LINE (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the A50 millimeter wave radar sensor assembly connector.
      GTY739849Courtesy 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
      A50-5 (CA1P) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      A50-6 (CA1N) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      A50-5 (CA1P) - E13-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      A50-6 (CA1N) - E13-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
    3. Connect the A50 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

  15. CHECK FOR SHORT IN CAN BUS LINE (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the E71 driving support ECU assembly connector.
      GTY688029Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 DLC3 - -
      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)      		 - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E71-8 (CA1P) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      E71-9 (CA1N) - E13-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      E71-8 (CA1P) - E13-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      E71-9 (CA1N) - E13-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
    3. Connect the E71 driving support ECU assembly connector.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY:  COMPONENTS [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE CAN BUS BRANCH LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - DRIVING SUPPORT ECU ASSEMBLY) 

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