I am by no means an expert in this, but I did help a friend with the same sort of problem, and I learned quite a bit.

The electronic transmission is really dumb. It won't do anything without a command from the ETM. The ETM looks at a bunch of things before it will issue a shift command: speed, engine RPM, throttle position, engine load, phase of the moon, etc. In my friend's case the problem was the vehicle speed sensor (right front wheel) had failed , and was telling the ETM that the car was not moving, so (of course) there would be no command to shift. This will, apparently, not generate a fault code in the ETM.

So my point is that it may not be the trans or the ETM, but one of the inputs that the ETM needs. If your indie doesn't know about this stuff, you need to take the car to a shop that does.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe