1995 E320 blower motor regulator
 

I have an intermittent working fan. Strangely when I make a hard right turn the blower motor starts working, soon as I straighten out of the turn it slows or dies. I'll do the brushes on the blower motor because that's easy enough (if I can find replacement brushes at a local motor supply shop). At first glance, the only way I see to get the brushes out is to pry the retaining metal that keeps the brushes in place. Any one care to chime in if there is something to unscrew or unbolt?
Regarding the regulator, I took it apart - to me it looks like a heat sink, no mechanical or moving parts to it. So I took it apart from the conducting wires that is held to it, gave it a thorough cleaning and put it back together. It made the blower motor work for about a week. Then it returned to its intermittent ways. What is it that actually goes bad on the regulator?

1995 E320
220k miles
been there, done that with most of the common repairs these cars need.

Heat cycles cause the electronic components to fail.

Won't hurt to check your fuse also. Maybe it is cracked but re-contacts on turns. (Long shot, I realize, but it is right there and easy to check.)