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Brake Control Warning Light does not Come ON [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check if CAN communication system DTCs are output. Refer to DIAGNOSIS SYSTEM [08/2013 - ] .

      Result

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

    B → See step   5 

    A: Go to next step 

  2. PERFORM ACTIVE TEST USING TECHSTREAM (BRAKE WARNING LIGHT / YELLOW (MINOR MALFUNCTION)) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Select the Active Test on the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2013 - ] .
      ABS/VSC/TRAC

      Tester Display Test Part Control Range Diagnostic Note
      ECB* Warning Light Brake warning light / yellow (minor malfunction) Warning light ON/OFF Observe combination meter assembly

      *: Electronically Controlled Brake System

    4. Check that the brake warning light / yellow (minor malfunction) on the combination meter assembly turns on or off in accordance with Techstream operation.

      OK

      The brake warning light / yellow (minor malfunction) turns on or off in accordance with Techstream operation.

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

    NG → See step   3 

    OK → See step   4 

  3. INSPECT COMBINATION METER ASSEMBLY 
    1. Turn the power switch off.
    2. Perform the Active Test of the combination meter assembly (meter CPU) using the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2013 - ] .
    3. Check the combination meter assembly.

      OK

      The brake warning light / yellow (minor malfunction) turns on or off in accordance with Techstream operation.

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

    NG → See step   6 

    OK → See step   4 

  4. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [08/2013 - ] 
  5. INSPECT CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ] 
  6. REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [08/2013 - ]