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DTC U1002: Lost Communication with Gateway Module (Sensor Bus); DTC U0235: Lost Communication with Cruise Control Front Distance Range Sensor [08/2015 - ]: Procedure

  1. RECONFIRM DTC OUTPUT 

    Reconfirm DTCs.

    Result

    Result Proceed to
    DTC U0104 is not output from the power management control ECU (Techstream display: PM1 Gateway) A
    DTC U0104 is output from the power management control ECU (Techstream display: PM1 Gateway) B

    B → Refer to   16 

    A: Go to next step 

  2. CHECK SUB BUS 13 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Measure the resistance according to the value(s) in the table below.
      GTY479541Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

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

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      L60-40 (CA1P) - L60-18 (CA1N) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω Below 54 Ω: Short circuit between bus lines
      70 Ω or more: Open circuit in main bus lines
      L60-40 (CA1P) - L60-25 (GND) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      L60-18 (CA1N) - L60-25 (GND) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANL ground short
      L60-40 (CA1P) - L60-30 (B) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      L60-18 (CA1N) - L60-30 (B) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANL +B short

      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

    B → Refer to   7 

    C → Refer to   9 

    D → Refer to   11 

    A: Go to next step 

  3. CHECK FOR POWER SOURCE CIRCUIT (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Check the millimeter wave radar sensor assembly power source circuit. Refer to DTC U0235: Lost Communication with Cruise Control Front Distance Range Sensor; DTC U1104: Lost Communication with Driving Support ECU [08/2015 - ] .

    NG → REPAIR OR REPLACE POWER SOURCE CIRCUIT (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

    OK: Go to next step 

  4. CHECK FOR DTC OUTPUT 
    1. Reconnect the cable to the negative (-) auxiliary battery terminal.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch on (IG).
    4. Turn the Techstream on.
    5. Clear the DTCs.
    6. Turn the power switch off.
    7. Turn the power switch on (IG).
    8. Check for DTCs.

      Result

      Result Proceed to
      DTC U1002 is not output from the driving support ECU assembly (Techstream display: Pre-Collision 2) A
      DTC U1002 is output from the driving support ECU assembly (Techstream display: Pre-Collision 2) B

    B → Refer to   5 

    A → Refer to   15 

  5. REPLACE DRIVING SUPPORT ECU ASSEMBLY 
    1. Replace the driving support ECU assembly. Refer to REMOVAL [08/2015 - ] .

    NEXT: Go to next step 

  6. CHECK FOR DTC OUTPUT 
    1. Reconnect the cable to the negative (-) auxiliary battery terminal.
    2. Turn the power switch off.
    3. Turn the power switch on (IG).
    4. Check for DTCs.

      Result

      Result Proceed to
      DTC U1002 is not output from the driving support ECU assembly (Techstream display: Pre-Collision 2) A
      DTC U1002 is output from the driving support ECU assembly (Techstream display: Pre-Collision 2) B

    B → Refer to   14 

    A → END 

  7. CHECK FOR OPEN IN SUB BUS 13 MAIN LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the L60 driving support ECU assembly connector.
      GTY474395Courtesy 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
      L60-40 (CA1P) - L60-18 (CA1N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG → Refer to   8 

    OK → Refer to   13 

  8. CHECK FOR SENSOR BUS MAIN LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Reconnect the L60 driving support ECU assembly connector.
    2. Disconnect the A70 millimeter wave radar sensor assembly connector.
      GTY482473Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *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
      A70-3 (CA1P) - A70-2 (CA1N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG → REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR 

    OK → Refer to   14 

  9. CHECK FOR SHORT IN SUB BUS 13 LINES (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the L60 driving support ECU assembly connector.
      GTY474395Courtesy 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
      L60-40 (CA1P) - L60-18 (CA1N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG → Refer to   10 

    OK → Refer to   13 

  10. CHECK FOR SHORT IN SUB BUS 13 LINES (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Reconnect the L60 driving support ECU assembly connector.
    2. Disconnect the A70 millimeter wave radar sensor assembly connector.
      GTY482473Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *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
      A70-3 (CA1P) - A70-2 (CA1N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG → REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR 

    OK → Refer to   14 

  11. CHECK FOR SHORT IN SUB BUS 13 LINE (DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the L60 driving support ECU assembly connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY474394Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

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

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      L60-40 (CA1P) - L60-25 (GND) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      L60-18 (CA1N) - L60-25 (GND) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANL ground short
      L60-40 (CA1P) - L60-30 (B) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      L60-18 (CA1N) - L60-30 (B) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANL +B short

    NG → Refer to   12 

    OK → Refer to   13 

  12. CHECK FOR SHORT IN SUB BUS 13 LINE (MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Reconnect the L60 driving support ECU assembly connector.
    2. Disconnect the A70 millimeter wave radar sensor assembly connector.
      GTY479609Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 DLC3
      *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 Result
      A70-3 (CA1P) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANH ground short
      A70-2 (CA1N) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Below 200 Ω: CANL ground short
      A70-3 (CA1P) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANH +B short
      A70-2 (CA1N) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Below 6 kΩ: CANL +B short

    NG → REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR 

    OK → Refer to   14 

  13. REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 
  14. REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 
  15. SYMPTOM SIMULATION. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] 
  16. GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC. Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2015 - ] 
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