On-Vehicle Inspection

INSPECT A/C PRESSURE SWITCH
1. Low and high pressure cut side:
  Inspect pressure switch operation.
  1. Set the manifold gauge.
  2. Connect the positive (+) lead from the ohmmeter to terminal 4 and the negative (-) lead to terminal 1.
  3. Check continuity between the terminals when refrigerant pressure is changed, as shown in the illustration.
    If operation is not as specified, replace the liquid tube sub-assembly.
    
    Fig 1: Inspecting Pressure Switch Operation (Low And High Pressure Cut Side)
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Middle pressure cut side:
  Inspect pressure switch operation.
  1. Set the manifold gauge.
  2. Connect the positive (+) lead from the ohmmeter to terminal 2 and the negative (-) lead to terminal 3.
  3. Check continuity between the terminals when refrigerant pressure is changed, as shown in the illustration.
    If operation is not specified, replace the liquid tube sub-assembly A.
    
    Fig 2: Inspecting Pressure Switch Operation (Middle Pressure Cut Side)
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002