Presentation and transmission problem

Moin Gemeinde, I would like to introduce myself as a Voyager newcomer. My name is Oliver very close to 50 and I come from Schleswig Holstein (Hademarschen). I have been screwing now since I have a driver’s license and come rather from the corner of the Youngtimer Benze. I can call 3 W124 my own and an 82er Opel record. Now I gave in to my wife’s wish and bought a Chrysler Grand Voyager 2.8 Diesel from 2005 Stow ́n Go with 230,000 km. As OBDII newcomer I tried to read out the onboard diagnosis with the 3 times ignition key method. 🙁 Unfortunately, does not work!? What am I doing wrong? Furthermore, the biggest problem is the automatic transmission. It switches so well, only there is a jerk in the gearbox after starting up each time. I think when it switches from the 1st to the 2nd gear. Does someone have a tip for me what that can be? The transmission oil is before just a paa r Thousand KM have been changed and nice reddish with correct filling level. Thank you in advance and greetings Oliver