I over heard a customer the other day stating' "Why are you charging me for scanning my car when it only took you less than a minute to plug in and see what is wrong?
The shop was busy and the service writer, who was new, didn't take the time to educate the customer on this all to common question. I would like to take the time to explain if you are wondering the same thing. It may look like it was a quick simple task, and i agree, but unless you know what's involved to do this service you don't have the full picture.
With out getting into a full blown course on the electronics of a vehicle, i will try and sum it up in a few sentences. Vehicle have various computers that regulate and monitor the operation of the section of the vehicle they were made for. Each computer has inputs and outputs to make the vehicle perform as the manufacturer designed it. If the computer sees any irregular activity outside it's perimeters, then it triggers a code (Which tells which system malfunctioned with a description), and is there until read and erased by the tech. The tool that is used to access the car computer is referred to as a scanner, or code scanner. Now there is a lot more to the operation,but that's the basics of operation.
My point here is why the cost! Here is why. The scanner itself can run $3000 or more. If the shop has the capability to program your computer than there is a cost for the shop for that. That is usually a monthly fee for the use of the service. Then you have updates for the scanner so it's able to communicate with the new systems as they come out. You need access to the latest repair information through another service for updates, recalls and wiring diagrams. Not to mention how that specific system functions. If you are working on import vehicle then there is an add on package for that the shop is responsible for. Technicians need to be trained on the new systems and again, that is normally at the shops expense, The list can go on and on. For the shop to recover some of the cost, they need to charge a fee, and that is why they charge what they do.
You have probably looked into sites like amazon and seen scanners for $100, or dongles that will hook up to your phone. These are great for checking codes for the home oner and have a purpose. But they are no substitute for the professional models by any stretch of the imagination. Even if you could read the codes then you would need the resourses to figure out what set the code and how to repair it.
If you are looking for a dongle to check codes i suggest this one by VEEPEAK. It's around $40 and you can get the app on your android phone. It works fairly well and is user friendly. Again it's good for looking at data and codes but is limited compared to what the professional scanners and trained technicians can accomplish.