You should never have to pay a dealer to read a code BUT be aware that all code readers are not the same.

You should never have to pay a dealer to read a code BUT be aware that all code readers are not the same.

I've had Volkswagens for most of this century, first a GTI, then a Passat and now a Macan (okay that's a Porsche but same parent company). I wouldn't think of putting the Macan on a second party code reader but that's because I can see most things on the computer so I don't need to. The Passat was another story. I had a sensor error and the OBD2 at the local garage could not read the code completely then erased it because - argggg. I had to wait for the code to re-appear then take it in to be read. Also, some faults didn't give codes that could be read by generic readers.

For older vehicles, OBD2 is a great tool.
http://www.androidcentral.com/test-driving-obd2-readers-and-android