My friend means to buy a car code reader,It can easily determine the cause of the Check Engine Light.He hope it will help him when his car gets broken unfortunately.He asked me to buy one for him.I checked in the web.
But now it has a problem.
there's some versions of obdmate code reader.As I know.There are:
OBDMATE OM510
OBDMATE OM580
OBDMATE OM500
OBDMATE OM520.
Which one is the best?
I just know that all of them fit most of cars.But I doubt whether it is true.

Help! Thanks!