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How To Proceed With Troubleshooting [10/2015 - 12/2017]: Procedure

WARNING: This page is about a different car, the 2017 Lexus RX 450h and 2016 Lexus RX 450h. However, it is still accessible from the selected car via links, so may be relevant.
  1. VEHICLE BROUGHT TO WORKSHOP 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  2

  2. INSPECT AUXILIARY BATTERY VOLTAGE 
    1. Measure the auxiliary battery voltage with the power switch off.

      Standard Voltage

      11 to 14 V

      If the voltage is below 11 V, replace or recharge the auxiliary battery before proceeding to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK CAN COMMUNICATION SYSTEM* 
    1. Using the Techstream, check that the CAN communication system is functioning normally.

      HINT: 

      Refer to CAN Bus Check in CAN Communication System.

      Refer to DIAGNOSIS SYSTEM [10/2015 - 08/2016] , or refer to DIAGNOSIS SYSTEM [08/2016 - 12/2017]

      OK

      CAN communication system is functioning normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - 08/2019] 

    Result: 

    OK 

    See step  4

  4. CHECK METER / GAUGE SYSTEM* 
    1. Use the Techstream to check if the meter / gauge system is functioning normally.

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

      Body Electrical > Combination Meter > Trouble Codes 

      Result

      Result Proceed to
      Meter / gauge system DTCs are not output A
      Meter / gauge system DTCs are output B

    Result: 

    GO TO METER / GAUGE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] 

    Result: 

    See step  5

  5. CHECK ELECTRONICALLY CONTROLLED BRAKE SYSTEM 
    1. Use the Techstream to check if the electronically controlled brake system is functioning normally.

      Refer to DTC CHECK / CLEAR [10/2015 - 08/2018]

      Chassis > ABS/VSC/TRAC > Trouble Codes 

      Result

      Result Proceed to
      Electronically controlled brake system DTCs are not output A
      Electronically controlled brake system DTCs are output B

    Result: 

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2015 - 08/2016]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2016 - 03/2018] 

    Result: 

    See step  6

  6. CHECK FOR DTCs (CRUISE CONTROL SYSTEM)* 
    1. Check for DTCs, and note down any DTCs that are output.

      Refer to DTC CHECK / CLEAR [10/2015 - 12/2017] 

      Powertrain > Cruise Control > Trouble Codes 

    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2015 - 12/2017] 

      Powertrain > Cruise Control > Clear DTCs 

    3. Recheck for DTCs. Try to reproduce the DTCs by duplicating the conditions indicated by the DTCs.

      Refer to DTC CHECK / CLEAR [10/2015 - 12/2017] 

      Powertrain > Cruise Control > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      DTCs are output B

    Result: 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2015 - 12/2017]  

    Result: 

    See step  7

  7. PROBLEM SYMPTOMS TABLE 

    HINT: 

    Refer to Problem Symptoms Table.

    Refer to PROBLEM SYMPTOMS TABLE [10/2015 - 12/2017] 

    Result

    Result Proceed to
    Fault is not listed in Problem Symptoms Table A
    Fault is listed in Problem Symptoms Table B

    Result: 

    See step  9

    Result: 

    See step  8

  8. OVERALL ANALYSIS AND TROUBLESHOOTING* 
    1. Data List / Active Test

      Refer to DATA LIST / ACTIVE TEST [10/2015 - 12/2017] 

    2. Road test

      Refer to ROAD TEST [10/2015 - 12/2017] 

    3. Terminals of ECU

      Refer to TERMINALS OF ECU [10/2015 - 12/2017] 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  9

  9. REPAIR OR REPLACE 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  10

  10. CONFIRMATION TEST 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    END