Date registered: Mar 2005
Vehicle: '01-E320 & 02-ST2
Location: John 15:18-19
Mentioned: 0 Post(s)
Quoted: 35 Post(s)
I think the first question is whether your cars have functional OBD-II ports. That was first a US standard and I am not sure if or when it might have been adopted in Europe. If you call local dealers with your VINs maybe they can tell you.
If you have OBD-II ports the only one of those with which I am familiar is the Actron and it works just fine. Getting codes is only part of the battle, though, since you have to translate the code to words and then interpret the words, the latter of which is the most important part. (And with the internet you can search for codes to find both translations and some interpretations, I posted MB codes in the 210 forum.) So the reader itself isn't as important at least from that perspective.
If you don't have OBD-II then at least for the MB you can go on ebay.de and search for carsoft multiplexer, that will plug in to the 38-pin service connector and do lots more than read codes. I don't know about compatibility with other makes, maybe the sellers have adapters or something.
Take care and enjoy the ride,
Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy; its inherent virtue is the equal sharing of misery. (Winston Churchill)