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Home >> Toyota >> 2012 >> Prius Two >> Repair and Diagnosis (Single Page) >> External Pages >> Different variant/trim >> Section 124 (Pre-Collision System (Plug-In) (Diagnostics - Introduction)) >> Pre-Collision System >> How To Proceed With Troubleshooting >> How To Proceed With Troubleshooting
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How To Proceed With Troubleshooting

WARNING: This page is about a different variant/trim than selected.

HINT: 

  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: Go to next step 

  2. CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK 

    NEXT: Go to next step 

  3. INSPECT AUXILIARY BATTERY VOLTAGE 

    Standard voltage

    11 to 14 V (Power switch off)

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

    NG → CHARGE OR REPLACE AUXILIARY BATTERY 

    OK: Go to next step 

  4. CHECK CAN COMMUNICATION SYSTEM 
    1. Use the Techstream to check if the CAN communication system is functioning normally. Refer to DIAGNOSIS SYSTEM .

      Result

      DTC Condition Proceed to
      CAN DTC is not output A
      CAN DTC is output B

      B → GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  5. CHECK FOR DTC 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .
      1. Record the DTCs.
    2. Clear the DTCs.
    3. Recheck for DTCs.
      1. Attempt to duplicate the malfunction and check if the DTCs are output again. Refer to DTC CHECK / CLEAR .

        Result

        DTC Condition Proceed to
        DTC is not output A
        DTC is output B
        No DTC is output, and malfunction cannot be duplicated or checked C

      B → GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART  

      C → GO TO SYMPTOM SIMULATION. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  6. PROBLEM SYMPTOMS TABLE 

    Refer to Problem Symptoms Table. Refer to PROBLEM SYMPTOMS TABLE .

    Result

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

    B → Go to step 8 

    A: Go to next step 

  7. OVERALL ANALYSIS AND TROUBLESHOOTING 
    1. Data List / Active Test. Refer to DATA LIST / ACTIVE TEST 
    2. Terminals of ECU. Refer to TERMINALS OF ECU 

      NEXT: Go to next step 

  8. ADJUST, REPAIR OR REPLACE 
    NOTE:

    If the millimeter wave radar sensor assembly is replaced, the beam axis of the sensor needs to be adjusted. Refer to ADJUSTMENT .

    NEXT: Go to next step 

  9. CONFIRMATION TEST 

    NEXT → END