I had a problem not so long ago, and during the problem this code would come up intermittently. the thread on the blades had actually worn out. it showed up when I was trying to mince some meat. my blades weren't spinning for some things and it sounded a bit off. HO said it may be caused by overloading at some stage, but I know this is not so in this case. they replaced the blades under warranty. there is an explanation of codes possibily on this website or in the TM manual, but i don't think that 52 was there - I'd recommend calling your GL.