Receiver Dryer: Service and Repair

Reservoir

• The reservoir is available in different versions, depending on version of vehicle.

• Up to 09/2004, reservoir brackets were installed which have transferred noise from A/C system operation to the body under certain conditions of operation (howling noises from engine compartment due to vibrations of the bracket during A/C system operation). As of 09/2004, production switched over gradually to an optimized bracket - G -.





• If an optimized bracket - G - is installed in vehicles which were produced up to 09/2004, the double bolt which secures nut - B - must be removed if necessary and installed again turned around 180 ° (longer side must face bracket), it may also be necessary that a longer version must be used for bolts - A -.

Removing

- Drain the refrigerant circuit.

- Remove the front bumper.

Remove the following components, depending on the vehicle.

- Remove the left headlight

- Remove the charge air cooler.

Continuation of work for all vehicles:

- Remove bolts - A - and disconnect refrigerant lines - B - and - C -.





• Depending on the version, you can remove the reservoir without the holder (in this case, do not remove screw - A - and nut - B -).

• Depending on the complaint and version, you can remove the reservoir without the holder; in this case ignore - items A, B, C, F -.





- Loosen the bolts - A - and nuts - B - (only if the bracket - G - is supposed to be removed).

- Loosen the refrigerant line bracket - F - from bracket - G - (only if the bracket - G - is supposed to be removed).

- Remove the reservoir - E - and bracket - G - (only if the bracket - G - is supposed to be removed).

- Loosen the screws - D - and remove the reservoir - E - from the bracket - G -.

• Seal open connections on the reservoir and line connections with suitable caps (to prevent dirt and moisture from entering).

• The reservoir version and the attachment of refrigerant lines differ depending on the engine version.

• Removed reservoir contains refrigerant oil which must be restored to refrigerant circuit.

Installing

• Before installing reservoir.

• Reservoir removed contains refrigerant oil which must be returned to refrigerant circuit (with new reservoir). Adjustment of the oil quantity depends on the nature of the problem. If the reservoir was damaged, e.g. during an accident (no refrigerant escaped, no moisture or dirt entered refrigerant circuit), A/C system can be serviced without the need for extensive repair work by weighing old and new reservoir. Add enough refrigerant oil to the new reservoir until it is the same weight as the one that was removed.

• Keep the new reservoir closed as long as possible; only remove caps immediately prior to installation (reservoir contains a desiccant bag which soon becomes saturated with moisture and thus unusable when reservoir is open).

• In case e.g. of an accident with the refrigerant, clean the refrigerant circuit if an unknown amount of refrigerant oil leaks out or dirt or moisture enters the circuit (irrigate).

• Connection at reservoir can be marked with "IN" (from evaporator) and "OUT" (to compressor).

Installation is carried out in the reverse order, when doing this note the following:

- Insert reservoir - E - in bracket - G -; note the anti-twist and secure mounting element - J -.





- Tighten the screws - D -.

• Tightening specification: 10 Nm.

- Place washer - C - on bolt - H -.

- Install the reservoir - E - with the bracket - G -.

- Insert the screws - A - and nuts - B -.

• Tightening specification: 10 Nm.

- Replace O-rings - D - and - E -.





- Check the guide ring - H - on the connections for both refrigerant lines - B - and - C - for damage.

- Insert the respective O-ring seal (- D - and - E -) in the groove - J - on the connections for both refrigerant lines - B - and - C -.

• Coat O-ring seals lightly with refrigerant oil before installing => [ Refrigerant Circuit O-Ring Seals ] Refrigerant Circuit O-Ring Seals.

- Connect refrigerant lines - B - and - C -.

- Install bolts - A -.

• Tightening specification: 10 Nm.

- Following attachment, check routing of refrigerant pipes. They must be inserted in holders provided and not make contact with other components.

- Re-install remaining components removed.

- Evacuate and re-charge refrigerant circuit.

- Check the DTC memory for the Climatronic Control Module (J255) A/C control head and erase any faults displayed if necessary.

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