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DTC U1002: Lost Communication with Gateway Module (Sensor Bus) (07/2015 -): Procedure

  1. CHECK SUB BUS 13 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Measure the resistance according to the value(s) in the table below.
      GTY659871Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H188-8 (CA1P) - H188-9 (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
      H188-8 (CA1P) - H188-28 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANH ground short
      H188-9 (CA1N) - H188-28 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANL ground short
      H188-8 (CA1P) - H188-7 (B) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short
      H188-9 (CA1N) - H188-7 (B) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANL +B short
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Driving Support ECU Assembly)

      Result

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

    Result:  B

    B 

    See step  3

    Result:  C

    C 

    See step  6

    Result:  D

    D 

    See step  10

    Result:  A

    A 

    See step  2

  2. RECONFIRM DTC OUTPUT 
    1. Reconnect the cable to the negative (-) battery terminal.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Clear the DTCs.
    6. Turn the engine switch off.
    7. Turn the engine switch on (IG) and recheck for DTCs.

      Result

      Result Proceed to
      U1002 is output from driving support ECU assembly
      (Techstream display: Pre-Collision 2)      		 A
      Other DTC is output. B

    Result:  A

    A 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  B

    B 

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART (07/2015 -) )

  3. CHECK FOR OPEN IN SUB BUS 13 MAIN LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the H188 driving support ECU assembly connector.
      GTY658833Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *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
      H188-8 (CA1P) - H188-9 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

    Result:  OK

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    See step  4

  4. CHECK FOR OPEN IN SUB BUS 13 MAIN LINES (NO. 3 CAN J/C) 
    1. Reconnect the H188 driving support ECU assembly connector.
    2. Disconnect the H189 No. 3 CAN junction connector.
      GTY617756Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 3 CAN Junction Connector)      		 *b to Driving Support ECU Assembly
      *c to Millimeter Wave Radar Sensor Assembly - -
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      H189-10 (CANH) - H189-21 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Driving support ECU assembly
      H189-11 (CANH) - H189-22 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Millimeter wave radar sensor assembly

      Result

      Result Proceed to
      OK A
      NG (to Driving support ECU assembly CAN main bus line) B
      NG (to Millimeter wave radar sensor assembly CAN main bus line) C

    Result:  A

    A 

    REPLACE NO. 3 CAN JUNCTION CONNECTOR 

    Result:  B

    B 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 3 CAN J/C - DRIVING SUPPORT ECU ASSEMBLY) 

    Result:  C

    C 

    See step  5

  5. CHECK FOR OPEN IN SUB BUS 13 MAIN LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Reconnect the H189 No. 3 CAN junction connector.
    2. Disconnect the A74 millimeter wave radar sensor assembly connector.
      GTY650740Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A74-5 (CA1P) - A74-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)

    Result:  OK

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 3 CAN J/C - MILLIMETER WAVE RADAR SENSOR) 

  6. CHECK FOR SHORT IN SUB BUS 13 LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the H188 driving support ECU assembly connector.
      GTY667969Courtesy 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
      H188-8 (CA1P) - H188-9 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)

    Result:  OK

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    See step  7

  7. CHECK FOR SHORT IN SUB BUS 13 LINES (NO. 3 CAN J/C) 
    1. Reconnect the H188 driving support ECU assembly connector.
    2. Disconnect the H189 No. 3 CAN junction connector.
      GTY685164Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 3 CAN Junction Connector)      		 *b to Forward Recognition Camera
      *c to Driving Support ECU Assembly *d to Millimeter Wave Radar Sensor Assembly
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      H189-9 (CANH) - H189-20 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Forward recognition camera
      H189-10 (CANH) - H189-21 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Driving support ECU assembly
      H189-11 (CANH) - H189-22 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Millimeter wave radar sensor assembly

      Result

      Result Proceed to
      OK A
      NG (to Driving support ECU assembly main bus line) B
      NG (to Millimeter wave radar sensor assembly main bus line) C
      NG (to Forward recognition camera branch line) D

    Result:  A

    A 

    REPLACE NO. 3 CAN JUNCTION CONNECTOR 

    Result:  B

    B 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 3 CAN J/C - DRIVING SUPPORT ECU ASSEMBLY) 

    Result:  D

    D 

    See step  9

    Result:  C

    C 

    See step  8

  8. CHECK FOR SHORT IN SUB BUS 13 LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Reconnect the H189 No. 3 CAN junction connector.
    2. Disconnect the A74 millimeter wave radar sensor assembly connector.
      GTY650742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A74-5 (CA1P) - A74-6 (CA1N) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)

    Result:  OK

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 3 CAN J/C - MILLIMETER WAVE RADAR SENSOR) 

  9. CHECK FOR SHORT IN SUB BUS 13 LINES (FORWARD RECOGNITION CAMERA) 
    1. Reconnect the H189 No. 3 CAN junction connector.
    2. Disconnect the T12 forward recognition camera connector.
      GTY635882Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      T12-6 (CANH) - T12-12 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Forward Recognition Camera)

    Result:  OK

    OK 

    REPLACE FORWARD RECOGNITION CAMERA 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (NO. 3 CAN J/C - FORWARD RECOGNITION CAMERA) 

  10. CHECK FOR SHORT IN SUB BUS 13 LINE (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the H188 driving support ECU assembly connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY614900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition Purpose
      H188-8 (CA1P) - H188-28 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANH ground short
      H188-9 (CA1N) - H188-28 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANL ground short
      H188-8 (CA1P) - H188-7 (B) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short
      H188-9 (CA1N) - H188-7 (B) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANL +B short
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Driving Support ECU Assembly)

      HINT: 

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 13 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 13 inspection.

    Result:  OK

    OK 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    See step  11

  11. CHECK FOR SHORT IN SUB BUS 13 LINE (CAN NO. 2 J/C) 
    1. Disconnect the H189 No. 3 CAN junction connector.
      GTY666706Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 DLC3 - -
      *a Front view of wire harness connector
      (to No. 3 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 Connected to Purpose
      H189-9 (CANH) - H29-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Forward recognition camera Below 200 Ω:
      CANH ground short
      H189-20 (CANL) - H29-4 (CG) Below 200 Ω:
      CANL ground short
      H189-10 (CANH) - H29-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Driving support ECU assembly Below 200 Ω:
      CANH ground short
      H189-21 (CANL) - H29-4 (CG) Below 200 Ω:
      CANL ground short
      H189-11 (CANH) - H29-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Millimeter wave radar sensor assembly Below 200 Ω:
      CANH ground short
      H189-22 (CANL) - H29-4 (CG) Below 200 Ω:
      CANL ground short
      H189-9 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Forward recognition camera Below 6 kΩ:
      CANH +B short
      H189-20 (CANL) - H29-16 (BAT) Below 6 kΩ:
      CANL +B short
      H189-10 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Driving support ECU assembly Below 6 kΩ:
      CANH +B short
      H189-21 (CANL) - H29-16 (BAT) Below 6 kΩ:
      CANL +B short
      H189-11 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Millimeter wave radar sensor assembly Below 6 kΩ:
      CANH +B short
      H189-22 (CANL) - H29-16 (BAT) Below 6 kΩ:
      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 Sub Bus 13 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 13 inspection.

      Result

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

    Result:  A

    A 

    REPLACE NO. 3 CAN JUNCTION CONNECTOR 

    Result:  B

    B 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 3 CAN J/C - DRIVING SUPPORT ECU ASSEMBLY) 

    Result:  D

    D 

    See step  13

    Result:  C

    C 

    See step  12

  12. CHECK FOR SHORT IN SUB BUS 13 LINE (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the A74 millimeter wave radar sensor assembly connector.
      GTY656796Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *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 Purpose
      A74-5 (CA1P) - H29-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANH ground short
      A74-6 (CA1N) - H29-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANL ground short
      A74-5 (CA1P) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short
      A74-6 (CA1N) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      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 Sub Bus 13 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 13 inspection.

    Result:  OK

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 3 CAN J/C - MILLIMETER WAVE RADAR SENSOR) 

  13. CHECK FOR SHORT IN SUB BUS 13 LINE (FORWARD RECOGNITION CAMERA) 
    1. Disconnect the T12 forward recognition camera connector.
      GTY617010Courtesy 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
      T12-6 (CANH) - T12-10 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANH ground short
      T12-12 (CANL) - T12-10 (GND) Cable disconnected from negative (-) battery terminal 200 Ω or higher Below 200 Ω:
      CANL ground short
      T12-6 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANH +B short
      T12-12 (CANL) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ:
      CANL +B short
      TEXT IN ILLUSTRATION

      *1 DLC3
      *a Front view of wire harness connector
      (to Forward Recognition Camera)

      HINT: 

      • It is only necessary to perform the inspection in the above table for the result (short circuit) that was obtained in the Check Sub Bus 13 inspection.
      • Find the necessary inspection from the Purpose column that matches the result in the Result column from the Check Sub Bus 13 inspection.

    Result:  OK

    OK 

    REPLACE FORWARD RECOGNITION CAMERA 

    (Refer to REMOVAL (07/2015 -) )

    Result:  NG

    NG 

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (NO. 3 CAN J/C - FORWARD RECOGNITION CAMERA) 

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