The earlier cars as well as turbos had the M46 which is a 4 speed manual
....which can fail too... The OD on my M46 stopped working exactly in the
same way as tlr1000's did. At first it popped out of the OD without
warning - that's pretty unconfortable - an later it stopped working. I found
out that the wiring from the relay to the switch on the transmission (or the
switch itself, havent'checked it yet) has a defect. I have made a new wire
from ground and connected it to the relay. This enables me to operate the OD
again - but now in all gears...! I must be very cautious and check the green
lamp, otherwise it will stress the OD. But it works until i have the time to
check under the car.