If you search for car wash near me or car wash nearby on sites such as findcarwashnearme.com, you will find that regardless of the car wash place, the steps followed are almost all the same. These are:
There is a pre-soak. This is done by an automated nozzle or it is done by a hand held spray. This is not found in all car washes however. Then there is the wash which consists of a high pressure spray or sometimes a cloth material can be used with a detergent solution as well. Then there is the rocker panel or the undercarriage which is taken care of. This is done by a cloth or high pressure sprays which are used on all sides as well as the bottom of the vehicle. When there is a conveyor type of mechanism, this is operated on the carriages or on independent arms and these spray upwards from either below the vehicle or from beside the vehicle.
After this is done is called the first rinse. This is usually with high pressure and water and the vehicle is rinsed. Then wax or sealers or even polishes can be used as an optional finish to the surface. These are sprayed onto the vehicle. Post this, the vehicle is given a final rinse which is at low pressure and this is either with fresh water or with deionizer water or it can be membrane filtered water. This is sprayed on the vehicle.
After this entire procedure, the vehicle has air blown over it so that water is removed as well as it is dried faster. There is also hand drying which can be done by the vehicle being wiped with chamois cloth or with towels.
This are the normal steps followed for professional car washes.