This morning my highbeams came on and then immediately went out. Both fuses for the highbeams are intact. I doubt both bulbs would have burned out at the same time. What else should I check?
Turns out BOTH high beam bulbs failed at the same time. Toyota says it's fairly common, although it's the first time I ever had it happen to me.
Sounds very strange, for both bulbs to go out simultaneously. The following is likely not applicable, but you don't disclose location: This isn't a Canadian car? They run high beams at reduced brightness as Daytime Running Light, and they're on whenever the headlights are off, not switchable. I noticed a while back our high beam bulbs have kind of a "tan". (A little hard to see.)
Bulbs should be replaced in pairs anyway. Now you don't have to feel like you're losing any value replacing both bulbs when only one failed. What probably happened is that both bulbs had filaments that were close to failing. When one filament failed, it caused a momentary surge on the circuit to the remaining bulb, which caused it to fail as well.
Had the same thing happen to a 76 Malibu Classic. Went out to drive one morning, both headlights were out. Checked a few things, bought some more headlights and problem was solved. Do you use your high beams a lot?
That was my theory as well. I don't think the "surge" would be much as each bulb has it's own circuit (fuse), but you never know. Pretty much every morning on the drive into town. Rural area, so I use them to see wildlife that might dart onto the road. Low beams just don't cut it. I think the low beams stay on when the high beams are on, and I'm surprised those haven't failed, BUT I know some types of bulbs provide more output at the cost of shorter lifespan, so the low beams might be good for a while longer before they fail.
I believe the low beams go off when high beams are on. I suppose we could solve this great mystery if some hardy soul went out and took a look, lol, but hey. Then again, with the 2016's there's only one (LED) head light, and low/high beam is accomplished by some paddle within the headlight that moves to change beam direction.
The lowbeam lights stay on when the highbeams are on. If you have factory foglights on, they will go off when the highbeams are turned on.
