I believe the cost for the star diagnostics? (computer that can hooks up to your ML to activate certain settings) costs like $10,000... Not worth the money, u're better off to bring it back to the dealer for AAM settings (rarely needed to be done), as for the OBD2 you better just get a obd2 cable + software that hooks up to your laptop cost is around $150, that can reset your check engine light (unplugging your battery works too to reset) and test your vehicles problems.. I used my shops snap on versus the laptop w/ obd2 cable and the laptop was far more superior as it provided me with graphs, full details on the error where as the Snapon only has 3 lines of led text (difficult to read and to buy the graph option is another $3K..)