ewecansew, There appears to be a website where you can ask a question of a Pfaff serviceman. If you have not gotten an answer to your question yet, perhaps you could try that.
http://www.justanswer.com/sip/pfaff?...FUid4AodBkoAFA
YIkes! I hope that link works.
edit: Looks like the link did work but when I pasted it in it was a long lot of numbers and letters. Hope you can solve your problem with this link.