Do a search and you'll find this topic has been discussed a number of times. Lots of good background in the archives.

As others have noted, if you JUST want to read OBD-II codes, any standard scanner will work thanks to Uncle Sam.

But, keep in mind that generic, inexpensive scanners will not let you see the Mercedes CAN or the diagnostic codes for many of the systems in the car. If you want to get into the detailed codes, its much more money.

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KenP

1996 S500 W140 Coupe