On 3/13/10 7:57 AM, Ed Pawlowski wrote:


wrote

You are assuming that his definition of "drive by wire" on his Saturn
excludes the operation of the transmission. Maybe it does, but he
didn't say one way or the other so we don't know.

Yes, we do know. Linkage is mechanical.




I can't say either way for sure as I do not have the shop manual yet (no
need for at least another 2 years). When the shifter is put in "M"
manual while the transmission is in any gear other than 1st the
transmission drops down a gear. If the car speeds up or down the
transmission will continue to shift albeit a little more aggressively (a
more sportier feel). If the shifter is put into "M" while the
transmission is in 1st or stopped the car will not shift until you
manually shift it with a toggle switch on the side of the shifter (sort
of a clutch-less manual mode - where all 6 gears are available). It is
this mode that makes me wonder as this has to be a by wire shift mode as
there is no movement of linkage only the pressing (rocking up or down)
of a toggle switch).

I know the computer plays a roll in the shifting because the shift
patterns can be changed by reprogramming the computer. I believe there
was a service bulletin for the 4 cylinder model that fixed a shift
pattern problem on the smaller engine. The solution was uploading a
patch to the computer.

From what I have read in a Saturn news group I believe the shifting is
by wire from the shifter but can not say if it goes to the computer
before the transmission or if the computer only monitors the
transmission and has the ability to make adjustments to performance?