On-Vehicle Inspection

WARNING: This page is about a different car, the 2004 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.

SET VEHICLE IN THESE CONDITION
1. Engine speed at 1,500 RPM
2. Blower speed control switch at "HI" position
3. Temperature control dial at "MAX. COOL" position
4. Manifold gauge set setting.
INSPECT PRESSURE SWITCH OPERATION
1. Disconnect the connector.
  
  Fig 1: Disconnecting Connector From Pressure Switch
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect pressure switch continuity (Magnetic Clutch Control)
  1. Connect the positive (+) lead from the ohmmeter to terminal 4 and the negative (-) lead to terminal 1.
  2. Check continuity between terminals when refrigerant pressure changes, as shown in the illustration.
If continuity is not as specified, replace the pressure switch.

Fig 2: Inspecting Pressure Switch Continuity (Magnetic Clutch Control)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002