I have a 2004 beetle that had the auto tiptronic transmission replaced prior to my purchase with a 2006 auto tiptronic. The check engine light is on and the seller said it had to due with the transmission change. It drives and shifts perfectly. It is showing a p 0841 code. The tiptronic magnets were missing, but they have been replaced and now the tiptronic works too. However, the engine light is still on. Should they have replaced the TCM to match the 2006 trans or could this be that maybe the fluid level is not correct? Maybe they didn't put in enough fluid or too much? Any help would be appreciated. I am not sure if you use a different year trans if you need to replace the tcm too.