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DTC U1002: Lost Communication with Gateway Module [10/2015 - ]: Procedure

  1. CHECK SUB BUS 
    1. Disconnect the cable from the negative (-) battery terminal.
      GTY656364Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Driving Support ECU Assembly)
      *b Front view of DLC3
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      N172-8 (CA1P) - N172-9 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω Below 53 Ω:
      Short in line
      N172-8 (CA1P) - N172-9 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω Higher than 70 Ω:
      Open in CAN main bus line
      N172-8 (CA1P) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 Ω:
      +B short
      N172-9 (CA1N) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      +B short
      N172-8 (CA1P) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      Ground short
      N172-9 (CA1N) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      Ground short

      Result

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

    Result: 

    B 

    See step  3

    Result: 

    C 

    See step  8

    Result: 

    D 

    See step  16

    Result: 

    A 

    See step  2

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

      Refer to DTC CHECK / CLEAR [10/2015 - ]

    2. Perform the following procedure.

      HINT: 

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

      1. Turn the engine switch on (IG) and wait 2 seconds or more.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2015 - ]

      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 [10/2015 - ] 

    Result: 

    B 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

  3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the forward recognition camera connector.
      GTY522374Courtesy 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
      Y17-6 (CANH) - Y17-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    See step  4

  4. CONNECT CONNECTOR 
    1. Reconnect the Y17 forward recognition camera connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CHECK FOR OPEN IN CAN BUS MAIN WIRE (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY532690Courtesy 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
      B17-5 (CA1P) - B17-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    See step  6

  6. CONNECT CONNECTOR 
    1. Reconnect the B17 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  7. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 6 CAN JUNCTION CONNECTOR) 
    1. Disconnect the No. 6 CAN junction connector.
      GTY642242Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 6 CAN Junction Connector)
      *b to Forward Recognition Camera
      *c 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 Result
      N132-8 (CANH) - N132-19 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Forward recognition camera
      N132-11 (CANH) - N132-22 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Millimeter wave radar sensor assembly

      Result

      Result Proceed to
      OK A
      NG (Millimeter wave radar sensor assembly CAN main wire) B
      NG (Forward recognition camera CAN main wire) C

    Result: 

    A 

    REPLACE NO. 6 CAN JUNCTION CONNECTOR 

    Result: 

    B 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

    Result: 

    C 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

  8. CHECK FOR SHORT IN CAN BUS WIRES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the forward recognition camera connector.
      GTY522374Courtesy 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
      Y17-6 (CANH) - Y17-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    See step  9

  9. CONNECT CONNECTOR 
    1. Reconnect the Y17 forward recognition camera connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  10

  10. CHECK FOR SHORT IN CAN BUS WIRES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY532690Courtesy 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
      B17-5 (CA1P) - B17-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    See step  11

  11. CONNECT CONNECTOR 
    1. Reconnect the B17 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  12

  12. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 CAN JUNCTION CONNECTOR) 
    1. Disconnect the No. 6 CAN junction connector.
      GTY646763Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 6 CAN Junction Connector)      		 *b to Forward Recognition Camera
      *c to Driving Support ECU Assembly *d 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 Result
      N132-8 (CANH) - N132-19 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Forward recognition camera
      N132-9 (CANH) - N132-20 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Driving support ECU assembly
      N132-11 (CANH) - N132-22 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Millimeter wave radar sensor assembly

      Result

      Result Proceed to
      OK A
      NG (Millimeter wave radar sensor assembly CAN main wire) B
      NG (Forward recognition camera CAN main wire) C
      NG (Driving support ECU assembly CAN branch wire) D
      NG (ECU or sensor CAN branch wires) E

    Result: 

    A 

    REPLACE NO. 6 CAN JUNCTION CONNECTOR 

    Result: 

    B 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

    Result: 

    C 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

    Result: 

    E 

    See step  15

    Result: 

    D 

    See step  13

  13. CONNECT CONNECTOR 
    1. Reconnect the N132 No. 6 CAN junction connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  14. CHECK FOR SHORT IN CAN BUS WIRES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the driving support ECU assembly connector.
      GTY637432Courtesy 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
      N161-8 (CA1P) - N161-9 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (DRIVING SUPPORT ECU ASSEMBLY - NO. 6 CAN JUNCTION CONNECTOR) 

  15. CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) 
    1. Reconnect the CAN junction connector.
      GTY674816Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Driving Support ECU Assembly)
    2. Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the short circuited branch line is connected.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N161-8 (CA1P) - N161-9 (CA1N) Cable disconnected from negative (-) battery terminal 54 to 69 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CORRESPONDING ECU OR SENSOR 

    Result: 

    NG 

    REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRE OR CONNECTOR 

  16. CHECK FOR SHORT IN CAN BUS WIRES (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the forward recognition camera connector.
      GTY532797Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
      *b Front view of DLC3
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Y17-6 (CANH) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      Y17-12 (CANL) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      Y17-6 (CANH) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      Y17-12 (CANL) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    See step  17

  17. CONNECT CONNECTOR 
    1. Reconnect the Y17 forward recognition camera connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  18

  18. CHECK FOR SHORT IN CAN BUS WIRES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY524107Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)
      *b Front view of DLC3
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B17-5 (CA1P) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      B17-6 (CA1N) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      B17-5 (CA1P) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      B17-6 (CA1N) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    See step  19

  19. CONNECT CONNECTOR 
    1. Reconnect the B17 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  20

  20. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 CAN JUNCTION CONNECTOR) 
    1. Disconnect the No. 6 CAN junction connector.
      GTY654490Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to No. 6 CAN Junction Connector)      		 *b Front view of DLC3
      *c to Forward Recognition Camera *d to Driving Support ECU Assembly
      *e 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 Result
      N132-8 (CANH) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher Forward recognition camera
      N132-19 (CANL) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N132-8 (CANH) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N132-19 (CANL) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N132-9 (CANH) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher Driving support ECU assembly
      N132-20 (CANL) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N132-9 (CANH) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N132-20 (CANL) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N132-11 (CANH) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher Millimeter wave radar sensor assembly
      N132-22 (CANL) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N132-11 (CANH) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N132-22 (CANL) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Result

      Result Proceed to
      OK A
      NG (Millimeter wave radar sensor assembly CAN main wire) B
      NG (Forward recognition camera CAN main wire) C
      NG (Driving support ECU assembly CAN branch wire) D
      NG (ECU or sensor CAN branch wires) E

    Result: 

    A 

    REPLACE NO. 6 CAN JUNCTION CONNECTOR 

    Result: 

    B 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

    Result: 

    C 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - FORWARD RECOGNITION CAMERA) 

    Result: 

    E 

    See step  23

    Result: 

    D 

    See step  21

  21. CONNECT CONNECTOR 
    1. Reconnect the N132 No. 6 CAN junction connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  22

  22. CHECK FOR SHORT IN CAN BUS WIRES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the driving support ECU assembly assembly connector.
      GTY670456Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)
      *b Front view of DLC3
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N161-8 (CA1P) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N161-9 (CA1N) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N161-8 (CA1P) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N161-9 (CA1N) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (DRIVING SUPPORT ECU ASSEMBLY - NO. 6 CAN JUNCTION CONNECTOR) 

  23. CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) 
    1. Reconnect the CAN junction connector.
      GTY656363Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Driving Support ECU Assembly)
      *b Front view of DLC3
    2. Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to +B, GND is connected.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N161-8 (CA1P) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N161-9 (CA1N) - N20-16 (BAT) Cable disconnected from negative (-) battery terminal 6 Ω or higher
      N161-8 (CA1P) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      N161-9 (CA1N) - N20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CORRESPONDING ECU OR SENSOR 

    Result: 

    NG 

    REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRE OR CONNECTOR 

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