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Auto High Beam function anomaly

Discussion in 'Prime Main Forum (2017-2022)' started by SR-71, Feb 2, 2019.

  1. SR-71

    SR-71 Member

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    As most know when commercial trucks pass each other on the highway many times the truck being passed will flash their high beams to let the passing truck know it has cleared them and it's safe for the passing truck to pull back over in front of the truck being passed. Vehicles sometimes give this same indication to passing trucks.

    On a recently trip my Prius Prime Advance model's auto high beam function nearly got me in an accident. Night time driving in the rain and a semi-truck was passing our Prius Prime Advanced. The reflections from the semi truck passing us caused our headlights to cycle from low beam to high beam and back to low beam again. Unfortunately the semi-truck hadn't totally passed our Prius yet but the truck driver mistook our flashing highlights as an indication it was safe to pull back over in front of us. Luckily I was able to get on the brakes and create enough space for the semi to over back over in front of us.

    After that close call I no longer use the auto head light function on multi-lane highways. This new technology is nice, but it can bite you.
     
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  2. Tideland Prius

    Tideland Prius Moderator of the North
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    Good to know. Didn’t know about the flash to indicate safe space.
     
  3. smyles

    smyles Active Member

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    Wait wait wait, truck was passing you and you had your highs on? In a rain??
     
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  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Thanks for the 'heads up' but I'll just make sure trucks no longer pass me. My lead-footed wife will be pleased.

    Bob Wilson
     
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  5. Buzzhead

    Buzzhead Non-Interference w/ devel of pre-Warp civs

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    Been doing that on the interstate since 78 (for me, anyway). Trucks used to thank you by cycling their running lights off and on. Not so much anymore.
     
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  6. padroo

    padroo Senior Member

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    There is so much traffic on interstates anymore there isn't much need for high beams except where the highways are separated by some kind of a barrier like trees or large distances between lanes.
     
  7. jaqueh

    jaqueh Active Member

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    Yeah I’m also confused. Auto high beams should never be used on multi lane interstate highways or freeways. And how did you get passed by a semi?!?!
     
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  8. Redthorne

    Redthorne Junior Member

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    Some of us that live out in the boonies have multi-lane highways separated by a planted median, and no highway lighting. The use of high beams is permitted by law (when lanes are separated by aforementioned median), and it is smart so you can see stuff like...animals in the road.

    However, if there's traffic coming up on my butt I do agree you should switch them off as soon as the passer is close.
     
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  9. SteveMucc

    SteveMucc Active Member

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    the fundamental problem is that the stupid switch to go between auto-high beam and normal is hidden and near impossible to find by hand alone. what a stupid, stupid place to put it.

    I have a slightly different issue... on the road leading up to my house there is a 120 degree turn at the bottom of a fairly steep decline. it's actually a pretty wide turn, but it sits directly on-top of a culvert and there are drop-offs on either side of the road. The fundamental problem is that approaching this at night you actually want to approach it with as much visibility as you absolutely can get. So I'll have the high beams on (this is also in a rural area, you can go a week without passing an oncoming car on this stretch of road), but as I'm approaching the turn the dang high-beams always turn themselves off (they do so automatically under 21 miles per hour). So either I have to fumble with the button or hold in the flash-to-pass in order to get sufficient light to make that turn safely (I live in a Bortle 2-3 area, so it's really, really dark out at night).

    I don't know why they didn't just make the auto-high beam a 4 position stalk or put the button on the steering wheel or stalk somewhere.

    i'm convinced they don't do any user interface testing at all.
     
  10. Dennis_MA

    Dennis_MA Active Member

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    I agree. I generally don’t use them for this exact problem.
     
  11. PT Guy

    PT Guy Senior Member

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    Toyota did a poor implementation of the auto high beam function. My Mazda does that job better. I stick to manual high beams in the Toyota.
     
  12. fuzzy1

    fuzzy1 Senior Member

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    They can disobey speed limits too, just as many other drivers do.
     
  13. pghyndman

    pghyndman Active Member

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    As a courtesy, I pull back from AHB mode as a vehicle in the passing lane is parallel to us, as I also do so preemptively when the beams of approaching vehicles crest a hilltop or curve. I don't like to be blinded, and other vehicles usually reciprocate (although as a stupid punk-nice person kid, if others did not oblige, I used to give 'em a warning blast of the eyeball melting airfcraft landing lamps mounted on my VW bug... great highway driving lamps when I was stationed in northern Maine).