Checking With Expansion Valve And Receiver/Dryer, Without Regulated A/C Compressor: Checking

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-- Turn off the ignition.

-- Connect pressure gauge battery (A/C service station).

-- Take pressure gauge readings. There are two possible results A and B.

Ambient Temperature in Degrees Celsius (Fahrenheit)	Pressure in Refrigerant Circuit in Bar (psi) Positive Pressure
15 °C (60 °F)	3.9 (57 psi)
20 °C (68 °F)	4.7 (68 psi)
30 °C (86 °F)	6.7 (97 psi)
40 °C (104 °F)	9.1 (132 psi)

A- The pressure in the refrigerant circuit is lower than the pressure specified in the table. There is not enough refrigerant in the circuit.

- Search for leak with leak detection device.

- The pressure release valve is open, check coolant fan activation according to the wiring diagram.

Check refrigerant pipes and hoses to see if they are bent too sharply (cross-section constrictions) or have external damage. If no malfunction is found, flush refrigerant circuit.

B - The pressure in the refrigerant circuit matches the table or is higher.

-- Start the engine.

-- Set A/C system to maximum cooling output.

-- Open doors.

-- Open vents in instrument panel.

The A/C compressor is driven by the engine via the magnetic clutch using the ribbed belt.

NOTE:

If the A/C compressor is not driven, check A/C Clutch -N25- voltage supply.

If the voltage supply is OK, repair the magnetic clutch.

If the A/C compressor is driven, check refrigerant circuit:

-- Bring engine speed up to 2000 RPM.

-- Observe manometer battery: