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If it were me I'd pay a few more and get one that tells you the code and its definition. With that one you'll need to look up the description in a booklet. Of course, you could memorize all of them if you have real good retention...
I never found any value in the reader telling me what the code is supposed to mean. There are usually a few that are incorrect and the best way to find a "fix" is type the code in on a site like this and start reading.