Air Conditioning Unit: Inspection

WARNING: This page is about a different car, the 2002 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.

Inspect Air Mix Servomotor
1. Inspect the air mix servomotor operation.
  1. Connect the positive (+) lead from the battery to terminal 7 and negative (-) lead to terminal 6, then check that the arm turns to "COOL" side smoothly.
    
    Fig 1: Checking Smooth Operation Of Arm To COOL Side Position
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Connect the positive (+) lead from the battery to terminal 6 and negative (-) lead to terminal 7, then check that the arm turns to "WARM" side smoothly.
    
    Fig 2: Checking Smooth Operation Of Arm To WARM Side Position
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  If operations are not as specified, replace the servomotor.
2. Inspect position sensor resistance.
  Measure resistance between terminals at servomotor arm each position as shown in the chart.
  
  Fig 3: Reviewing Servomotor Resistance Information
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 4: Determining Resistance Based On COOL & WARM Condition
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
If resistance is not as specified, replace the servomotor.
Inspect Evaporator
1. Check evaporator fins for blockage.
  If the fins are clogged, clean them with compressed air.
  
  NOTE: Never use water to clean the evaporator.
2. Check fitting for cracks or scratches.
If necessary, repair or replace.
Inspect Heater Radiator
Inspect fins for blockage.

If the fins are clogged, clean them with compressed air.