My 2010 TCH has an automatic night rear mirror darkening function. It doesn't seem to get as dark from rear car headlight reflections as a manual one. Is this normal? My Tpyota dealer put his fingertip into a small hole in the left front of the mirror and it darkened a little, but, in my opinion, not enough to be useful (especially if someone has brights on behind me. Any suggestions to cure the problem,short of putting on a manual one??

 

What you are seeing is normal, and is the reason I hate auto-darkening mirrors (I have very sensitive eyes). The only solution I found was to replace the mirror with a manual flip-type which I bought at O'Reilly's for a few bucks. Much better! I saved the auto-darkening one so I can put it back in before I trade in the car.