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Home >> Toyota >> 2012 >> Prius Two >> Repair and Diagnosis (Single Page) >> External Pages >> Different variant/trim >> Section 5 (Air Conditioning System (Plug-In) (Diagnostics - Introduction)) >> Air Conditioning System >> Diagnosis System >> Diagnosis System
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Diagnosis System

WARNING: This page is about a different variant/trim than selected.
  1. DESCRIPTION 
    1. Air conditioning system data and Diagnostic Trouble Codes (DTCs) can be read through the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform troubleshooting.
  2. CHECK DLC3 
    1. Check the DLC3. Refer to GENERAL INFORMATION .
  3. LIST OF OPERATION METHODS 
    1. By operating each of the air conditioning control switches as shown in the diagram below, it is possible to enter diagnostic check mode.
      Fig 1: Identifying List Of Operation Methods Diagram
      GTY328006Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INDICATOR CHECK 
    1. Turn the power switch off.
    2. Turn the power switch on (ACC) and wait for at least 5 seconds.
    3. Turn the power switch on (IG) while pressing the air conditioning control assembly "AUTO" switch and "Recirculation/Fresh" switch simultaneously. Hold both switches until the indicator check screen appears.
      Fig 2: Identifying AUTO & Recirculation/Fresh Switches
      GTY325598Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. The indicator check is automatically performed when panel diagnosis is activated. Check that the indicators light up and go off 4 times at 1-second intervals continuously.
      Fig 3: Identifying Indicator Lamps
      GTY329896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

      • The sensor check automatically starts when the indicator check is completed.
      • Press the "OFF" switch to cancel the check mode.
      TEXT IN ILLUSTRATION

      *a Indicator Blinking Pattern
      *b ON
      *c OFF
      *d 1 sec.
  5. SENSOR CHECK (DTC CHECK) 
    1. Start the engine and warm it up.
    2. Perform the indicator check.

      HINT: 

      After the indicator check is completed, the system enters DTC check mode automatically.

    3. Read the DTC displayed on the air conditioning control assembly.
      Fig 4: Identifying DTC
      GTY342746Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      In sensor check mode, which is automatically entered after indicator check mode, troubleshooting may be partially performed. Be sure to perform the sensor check again.

      HINT: 

      Refer to Diagnostic Trouble Code Chart for details of the codes. Refer to DIAGNOSTIC TROUBLE CODE CHART .

      • When there are no problems, DTC 00 is output.
      • As an example, the illustration shows that DTC 12 is output.
      TEXT IN ILLUSTRATION

      *a Diagnostic Trouble Code (DTC)
    4. If the DTCs are difficult to read because they change automatically, press the "MODE" switch to display the DTCs one at a time so that they can be read easily. The DTCs are displayed step by step each time the "MODE" switch is pressed.
      Fig 5: Identifying MODE Switch
      GTY338211Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

      Press the "OFF" switch to finish panel diagnosis.

    5. Clear the DTC
      1. During the sensor check, press the "FRONT DEF" switch and "MODE" switch simultaneously.
        Fig 6: Identifying FRONT DEF & MODE Switches
        GTY332362Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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