Joe Weinstein

Hi all,
I'm asking around. My car will be in the shop anyway so maybe it's time
to spruce it up... I heard a rumor there was an available update to the
PSM system for the early 996tts... Can anyone corroborate that?

pete95zhn

No there's not, from Porsche parts bin atleast. First turbos used different Drehratensensor ie. "Yaw angle" sensor, which only communicates with certain ABS/PSM unit. Bosch brought a new sensor to MY '02 and works with all ABS/PSM units since. The programming is the same, or at least if you replace malfunctioning '02 unit with '04 unit it's just told if it's in tiptronic or manual car. Wiring looms are identical.
Carreras with PSM's work evolved similarily, first C4's got PSM '99 and that 1st gen unit/sensor set was used until '01. '02 it was replaced with 2nd gen.

And there's one more thing, 2WD Motronic requires a 2WD PSM unit and 4WD Motronic a 4WD unit.

Joe Weinstein

OK, thanks.