AC compressor

What it does

Pumps refrigerant around the air conditioning system.

Signs it needs replacing

• AC blows warm air
• Loud noise when the AC is switched on
• Compressor clutch does not engage

What to tell the shop

• Vehicle make, model and model year
• Engine size, and whether it is manual or automatic
• The number printed on the old part, or a photo of it
• Whether you want genuine, OEM or a local replacement