Check that the terminals are clean, and the batteries are in the right way to. It's easy to have a brain f**t. My engineer other half just put a triple A battery in a folding Ott light the wrong way. He spent 5 minutes telling me the light was no good. Put the battery in the right way.
If you don't have the manual, here's a link. It reads online.
http://sewingonline.co.uk/instructions/pfaff1475cd/
Here's another page to see if there is any info. Most of the links to embroidery sites are dead.
http://www.cyberport.net/users/milne...#anchor1270222
You might have to call a dealer.