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Home >> Toyota >> 2012 >> Prius Two >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 129 (Pre-Collision System (Plug-In) (Diagnostic Codes & Circuit Tests)) >> Pre-Collision System >> DTC C1A4A: Skid Control Buzzer Circuit >> Procedure
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DTC C1A4A: Skid Control Buzzer Circuit: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. PERFORM ACTIVE TEST USING TECHSTREAM (SKID CONTROL BUZZER) 
    1. Select the Active Test, use the Techstream to generate a control command, then check that the skid control buzzer sounds. Refer to DATA LIST / ACTIVE TEST .
      ABS/VSC/TRAC

      Tester Display Test Part Control Range Diagnostic Note
      Buzzer Skid control buzzer sounds ON/OFF -

      OK

      Skid control buzzer sounds.

    NG → See step   4 

    OK: Go to next step 

  2. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER 
    1. Replace the brake booster with master cylinder (skid control ECU). Refer to REMOVAL .

    NEXT: Go to next step 

  3. CHECK DTC OUTPUT (PRE-COLLISION SYSTEM) 
    1. Using the Techstream, enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    3. Recheck for DTCs.

      OK

      DTC C1A4A is not output.

    NG → See step   5 

    OK → END (SKID CONTROL ECU ASSEMBLY WAS DEFECTIVE) 

  4. GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
  5. REPLACE DRIVING SUPPORT ECU. Refer to  REMOVAL