Code P1704 and P1603
 

Having fun :) with new(to me) 2002 Boxster S Tiptronic, and at this moment I use 'fun' loosely :confused: . I have been fighting various P codes having to do with Air intake and such. I fix one and then another that has been masked pops up, anyway I digress.
Just last week I started getting P1704 Kick-down switch and it won't go away. Now getting P1603 CAN timeout PSM not sending information. I have been using Durametric software and it's been well worth the $$'s, able to see many things that need looking at. The car has 132000+ miles but body and interior in excellent shape, also got it for reasonable price. It's getting a little frustrating since I had little to no trouble with my '84 TL for the five years I owned it, but again I digress.
I haven't been able to find any information on those two codes. I should add that the shifting has become a little erratic. I can put it in 'Manual' mode and shift but when in 'Auto' it will not shift up properly all the time.
I have been reading about changing the Oil, since I don't know if it's ever been done and the mileage indicates it probably should be changed.
Any help would be greatly appreciated.
Thanks,

i haven't had to mess with a tiptronic yet but here's some tests that you could do that are from the porsche electric workshop manual; perhaps they can be useful for you. ive heard changing the oil&filter in there solves some guys problems too.

http://forums.pelicanparts.com/uploa...1404013651.jpg
http://forums.pelicanparts.com/uploa...1404013666.jpg

id try out the trans oil& filter change just for the sake of it & so you can inspect the fluid for anything nightmarish but id also do those tests just so you can go through the system with the muilitmeter to confirm or eliminate anything.

i have some bits to the electric workshop manual so if your maybe looking for a page get at me :p

a little off topic, i got a 01 986 s that im working with that has a misfire i cant seem to peg; yet anyway. i posted a thread on it a couple nights back under 7.2 DME imput signals. i was seeing if you can perhaps help me out with sharing some data of your actual values& imput signals; it would be cool to have another cars values for comparisonSmileWavy
get at my thread if you canSmileWavy