Rear Expansion Valve, Disconnecting and Connecting

Rear Expansion Valve, Disconnecting and Connecting

• After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).

• There are different versions of the expansion valve (and thus different refrigerant lines to the expansion valve) depending on the production period. Therefore, ensure proper allocation using Electronic Parts Catalog.

Removing

- Discharge the refrigerant circuit.

- Depending on vehicle equipment, remove fitted foam section under left luggage compartment lining. or pressure reservoir of air spring suspension system.

• Pressure reservoir of air spring suspension system is not removed, pressurized air system is not opened, therefore make sure that pressurized air line is not kinked, yanked or otherwise damaged.

• So that the pressure reservoir can be detached and set aside, the emergency wheel or the Bass Loudspeaker (R100) must be removed, depending on vehicle equipment.

- Through the opening under left luggage compartment lining, remove bolts - A - (tightening torque 10 Nm).






- Disconnect refrigerant lines - B - and - C -.

• Close all open lines and connections on expansion valve with suitable caps (avoid dirt and moisture from entering the system).

Installing

- Replace O-rings - D - and - E -. For correct version, refer to Electronic Parts Catalog.

- Check fitted pin - G - (installed in low pressure line connection or in expansion valve - F -, not installed at all connections) and sleeves - H - of refrigerant lines for damage and proper seating.

• Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to => [ Refrigerant Circuit O-Rings ] Refrigerant Circuit O-Rings.

• Check O-ring seals for proper seating in groove - J - of respective refrigerant line

• Install refrigerant pipes such that they are not strained.

• Check installation position of refrigerant lines to expansion valve (they should not come in contact with other components).

- Insert refrigerant lines into expansion valve.

- Install bolts - A - (tightening torque 10 Nm).

- Install remaining components.

- Evacuate and re-charge refrigerant circuit.

- Operate the A/C system after filling the refrigerant circuit, refer to => [ A/C System, Operating after Filling Refrigerant Circuit ] A/C System, Operating after Filling Refrigerant Circuit.