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DTC U0104-87: Lost Communication with Cruise Control Module Missing Message [11/2018 - ]: Procedure

WARNING: This page is about a different car, the 2020 Toyota Mirai and 2019 Toyota Mirai. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR DTCs 
    1. Using the Techstream, check for front radar sensor system DTCs and pre-collision system DTCs and output pattern according to the following table.

      Body Electrical > Front Radar Sensor > Trouble Codes 

      Body Electrical > Pre-Collision System > Trouble Codes 

      Pattern Display on Techstream / Output DTC
      Front Radar Sensor system Pre-Collision System
      Pattern 1 U0104-87 U0235-87
      Pattern 2 U0104-87 -

      Result

      Result Proceed to
      Output in pattern 1 A
      Output in pattern 2 B

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  2

  2. CHECK CAN BUS LINES (FORWARD RECOGNITION CAMERA - DLC3) 
    1. Disconnect the forward recognition camera connector.
      GTY922097Courtesy 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
      W13-6 (CANH) - W13-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      W13-6 (CANH) - G8-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      W13-12 (CANL) - G8-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      W13-6 (CANH) - G8-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      W13-12 (CANL) - G8-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
    4. Connect the forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (FORWARD RECOGNITION CAMERA - DLC3) 

    Result: 

    OK 

    See step  3

  3. CHECK CAN BUS LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - DLC3) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY906320Courtesy 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
      A66-5 (CA1P) - A66-6 (CA1N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A66-5 (CA1P) - G8-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      A66-6 (CA1N) - G8-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      A66-5 (CA1P) - G8-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A66-6 (CA1N) - G8-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
    4. Connect the millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN BUS MAIN LINE OR CONNECTOR (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - DLC3) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (FORWARD RECOGNITION CAMERA - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the W13 forward recognition camera connector.
    2. Disconnect the A66 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
      W13-6 (CANH) - A66-5 (CA1P) Always Below 1 Ω
      W13-12 (CANL) - A66-6 (CA1N) Always Below 1 Ω
      W13-6 (CANH) or A66-5 (CA1P) - Body ground and other terminals Always 10 kΩ or higher
      W13-12 (CANL) or A66-6 (CA1N) - Body ground and other terminals Always 10 kΩ or higher
    4. Connect the W13 forward recognition camera connector.
    5. Connect the A66 millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN BUS LINE OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (FORWARD RECOGNITION CAMERA - POWER SOURCE CIRCUIT) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the forward recognition camera connector.
      GTY854105Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      W13-10 (GND) - Body ground Always Below 1 Ω
    4. Connect the cable to the negative (-) battery terminal.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      W13-7 (IGB) - Body ground Power switch off Below 1 V
      W13-7 (IGB) - Body ground Power switch on (IG) 11 to 14 V
    6. Connect the forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - POWER SOURCE CIRCUIT) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the millimeter wave radar sensor assembly connector.
      GTY912765Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (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
      A66-1 (SGND) - Body ground Always Below 1 Ω
    4. Connect the cable to the negative (-) battery terminal.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A66-8 (IGB) - Body ground Power switch off Below 1 V
      A66-8 (IGB) - Body ground Power switch on (IG) 11 to 14 V
    6. Connect the millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY 
    1. Replace the millimeter wave radar sensor assembly with a new one.

      Refer to REMOVAL [11/2018 - ]

    2. Perform millimeter wave radar sensor assembly adjustment.

      Refer to ADJUSTMENT [11/2018 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  8

  8. CHECK FOR DTCs 
    1. Clear the DTCs.

      Body Electrical > Front Radar Sensor > Clear DTCs 

    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.

      Body Electrical > Front Radar Sensor > Trouble Codes 

      Result

      Result Proceed to
      DTC U0104-87 is not output A
      DTC U0104-87 is output B

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  COMPONENTS [11/2018 - ] 

  9. CHECK CONNECTOR (FORWARD RECOGNITION CAMERA) 
    1. Check the locking part and terminals of the forward recognition camera connector.
      NOTE:
      • Make sure the connector is not loose or disconnected.
      • Make sure that the connector and terminals are not deformed or corroded.

      OK

      The connector and terminals are normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (FORWARD RECOGNITION CAMERA) 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (FORWARD RECOGNITION CAMERA POWER SOURCE CIRCUIT) 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the forward recognition camera connector.
      GTY896485Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Forward Recognition Camera)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      W13-10 (GND) - Body ground Always Below 1 Ω
    4. Connect the cable to the negative (-) auxiliary battery terminal.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      W13-7 (IGB) - Body ground Power switch on (IG) 11 to 14 V
    6. Connect the forward recognition camera connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (FORWARD RECOGNITION CAMERA POWER SOURCE CIRCUIT) 

    Result: 

    OK 

    See step  11

  11. INSPECT FORWARD RECOGNITION CAMERA (WAVEFORM) 
    1. Turn the power switch off.
    2. Disconnect the millimeter wave radar sensor assembly connector.
    3. Turn the power switch on (IG).
    4. Using an oscilloscope, measure the waveform at millimeter wave radar sensor assembly connector.
      GTY899401Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)      		 *b Waveform

      Measurement Condition

      Tester Connection Switch Condition Tool Setting
      A66-5 (CA1P) - Body ground Power switch on (IG) 1 V/DIV., 100 μs/DIV.
      NOTE:

      The oscilloscope waveform is for reference only and does not include noise, fluctuations, etc.

      OK

      A waveform similar to that in the illustration can be observed.

    5. Connect the millimeter wave radar sensor assembly connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  COMPONENTS [11/2018 - ] 

    Result: 

    NG 

    REPLACE FORWARD RECOGNITION CAMERA. Refer to  COMPONENTS [11/2018 - ] 

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