This valve is located in your ac compressor and is held in with a circlip. It controls when your ac turns on and off. If your ac compressor is not working change this valve before you change your compressor. You need check your compressor for the brand and model. This valve is compatible with: Valeo DCS17E & DCW17F Compressors. *** This does not go by year make and model as VW uses different brand compressors within the same model.***