2012 Toyota Prius Plug-inFACTORY OEM SERVICE PROCEDURE

How To Proceed With Troubleshooting

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

HINT: 

  • Use the following procedure to troubleshoot the LIN communication system.
  • *: Use the Techstream.
  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: Go to next step 

  2. CUSTOMER PROBLEM ANALYSIS 
    • In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
    • Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
    • The following 5 items are important points in problem analysis:
    What Vehicle model, system name
    When Date, time, occurrence frequency
    Where Road conditions
    Under what conditions? Driving conditions, weather conditions
    How did it happen? Problem symptoms

    NEXT: Go to next step 

  3. INSPECT BATTERY VOLTAGE 
    1. Measure the battery voltage with the power switch off.

      Standard Voltage

      11 to 14 V

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

      NEXT: Go to next step 

  4. CHECK COMMUNICATION FUNCTION OF LIN COMMUNICATION SYSTEM* 
    1. Using the Techstream, inspect the LIN communication function to ensure there are no malfunctions in the communication system. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      DTC is not output A
      DTC is output B

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

      A: Go to next step 

  5. PROBLEM SYMPTOMS TABLE 
    1. 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   7 

      A: Go to next step 

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

      NEXT: Go to next step 

  7. REPAIR OR REPLACE 

    NEXT: Go to next step 

  8. CONFIRMATION TEST 

    NEXT → END 

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.