Why won't my mixer turn on?

My issues were that it 1st - only ran on one speed, then 2nd, wouldn't turn on at all. The problem (I think) ended up being two loose bolts in the back housing behind the switch controller. When I took off the back cover, they just fell out. I couldn't find any photos of what the assembly should have looked like, so it was trial and error testing. Once I put the loose bolts back on the “hidden” posts/screws on the far back metal plate and tightened them down (and undid all the other adjustments I tried to make first) it worked like a champ.

Applies to models that tilt and that have a circuit breaker: Upon accessing the breaker from the underside of the stand, I found the white wire disconnected. Apparently the wire was under tension when the user tilted the head upward, until it finally broke. I reattached it, but used solder and heat-shrink tubing to insert an extra thumb-length of wire to prevent tension when tilted. Now it works perfectly.