E300 downshift switch

[zonezapper]

My friend has two problems;
Problem 1; He can't get the passing gear to kick in. He changed the transmission because of other problems.
He has changed the overload switch on the transmission. He also changed the computer and still has problem.

Problem 2; The cruise won't work. Can this be related ?

Where in the archives can I find the info on how to make the dianostic tool and how to access the codes?

Thanks, Tom Wiggins

My own mecdes;
84 190, 2.2 diesel 194k
and too many others to list!