it is not really obd 1 it is mercedes own propiotary connector, launch x431 is good but is $2000, but works on lots of car's. A chinese copy of the factory SDS (star diagnostic tester) is available on ebay for less than $1000 with a hard drive that is pre programed with the factory software. The hardrive must be used in an IBM T30 laptop about $200 on ebay.