Expansion Valve: Service and Repair

Remove or Disconnect
1. Evaporator from vehicle. Refer to Evaporator.

Inspect

Tool Required:
J 39183-C R-134a Manifold Gage Set

Expansion Valve Operation:

1. Connect the expansion valve to a J 39183-C; connect the gages set's charging hose to a Refrigerant-134a refrigerant drum.
2. Soak the valve's remote bulb in water.
3. Close both the high and low-pressure valves.
4. Open the valve to the refrigerant drum.
5. Open the high-pressure valve to approximately 5 kg/sq. cm (70 psi).
6. Read the pressure indicated on the low-pressure gage, and measure the water temperature with a thermometer.

Expansion Valve Pressure/Temperature Relationship Chart:

7. The pressure/temperature relationship should fall within the specifications shown. Otherwise, replace the expansion valve.

Install or Connect

8. Evaporator to vehicle. Refer to Evaporator.