Compressor HVAC: Description and Operation

Compressor Drive Unit

• If drive plate overload protection activates, check compressor for ease of motion before replacing the drive unit. If compressor creates friction, replace it completely.

• On vehicles with an 8 cylinder FSI engine, the A/C compressor is driven by an input shaft and not by a belt.






1 - Compressor Input Shaft

• Tightening specification: 60 Nm

• Check, the input shaft must be seated free of play in splines of engine drive wheel with thread tightened, refer to => [ Compressor Input Shaft ] Compressor Input Shaft.

• Loosening and tightening, refer to => [ Compressor Input Shaft, Loosening and Tightening ] Compressor Input Shaft, Loosening and Tightening.

• Removing and installing, refer to => [ Compressor Input Shaft ] Compressor Input Shaft.

• Grease the splines to the engine drive wheel with grease (G 000 100). Refer to the Electronic Parts Catalog.

2 - Hex Socket Head Bolt

• Tightening specification 10 Nm

3 - Drive Plate

• Run-out, checking and adjusting, refer to => [ Drive Plate Run-Out with Overload Protection, Checking and Adjusting ] Adjustments.

• Removing and installing, refer to => [ Drive Plate with Overload Protection ] Drive Plate With Overload Protection.

4 - Drive Plate

• Tightening specification 30 Nm

• Attached to compressor input shaft.

• With overload safeguard, triggers when torque is too-high (for example, compressor produces friction) and driveshaft runs freely without driving the compressor.

• Removing and installing, refer to => [ Drive Plate ] Drive Plate.

5 - Rubber Element

• Decouples drive unit, dampens vibrations and noises.

• When installing, coat rubber element lightly using, for example, soapy water (as sliding compound).

• Removing and installing, refer to => [ Drive Plate ] Drive Plate.

6 - Spacer

• The original disc must be installed.

• Dimension: 17.5 x 10 x 3 mm

7 - Circlip

• Replace

• Install on proper side (level side to compressor).

• Removing and installing, refer to => [ Drive Plate with Cylindrical Roller Bearing ] Drive Plate With Cylindrical Roller Bearing.

8 - Drive Plate

• With roller bearing.

• Removing and installing, refer to => [ Drive Plate with Cylindrical Roller Bearing ] Drive Plate With Cylindrical Roller Bearing.

• Clean compressor flange before sliding on drive plate.

9 - Compressor

• Different versions may be installed, depending on engine version and country version of vehicle. Refer to the Electronic Parts Catalog.