Automatic High Beams Not Functioning?

Is the sensor clean? Windscreen clean in front of the Forward Recognition Camera?

TOYOTA advise these conditions need to be correct for it to work:

 

Yeah, I have the same problem on my PRIME Premium, which is very similar to Gen4 Three trim. Didn't know Gen4 One had automatic high beams. Anyway, my auto high beam also goes wacky sometimes, not all the time, and I can not reproduce it at will nor do I know exactly what triggers this malfunction. When this happens to my car, high beam is disabled. I can't even turn on the high beam manually. Only way I have figured out to correct this problem for me is to turn off the auto high beam switch and stop car and start car again and turn back on the auto high beam. I can sometimes accomplish correcting it without actually stopping car by just toggling auto high beam switch on and off several times, but this does not work always. I have 20K service appointment next week, so I am going to mention this to my dealer, but since it is not reproducible, I have a feeling they will not be able to solve the puzzle. I will let you know if I find out anything at dealer.

 

There was another thread in the c forum with a similar symptom recently-

In that case, the driver had the headlights inadvertently set to DRL mode. This made the headlights appear to be on as low-beams, but the high-beams would not switch on in either auto or manual modes. Turning the headlights on fixed it.

 

Well, not sure for OP's Gen4 One trim, but for my PRIME Premium, there is no DRL ON mode. It only have DRL OFF (all headlights, side marker, parking, LED accent off), AUTO, side marker only, Headlight ON. I keep mine on AUTO most of the time, but this Auto High Beam problem occurred either on AUTO position or Headlight ON position.

 

Similar problem here. Sometimes it fails to turn the high beams back on, and then a couple vehicles later it starts working again. So etimes I press the button to turn it off and back on.

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The other thing is that it'll default to OFF when it gets what could be a false positive - like going under an overpass or past a large roadsign, it gets a lot of reflected light - and turns the High Beam OFF.

 

It is just not false positive shut off. I just drove back home in PRIME with AUTO High Beam ON and using high beam with headlight ON position, and encountered what have been described by OP and me above. With this error, not only high beam is OFF, it becomes unavailable by manual high beam switch. While I am driving with Auto High Beam, all the sudden the Auto High Beam shut itself off, and returns to low beam. At this point, Auto High Beam icon is turned off, and if I pull on the light lever, I can't get high beam to come on. This time I was able to toggle the switch and high beam lever switch several times to recover the high beam again without stopping the car.

 

So you can't even flash high beam by pulling toward you? That certainly sounds like a fault.

 

Flashing high beam works. By pulling the light lever, high beam would turn on as long as you hold the lever in that position, but it returns to middle on it's own if you let go, and that turns off high beam. Pushing lever forward to turn on high beam does not work and light stays low beam even though Auto High Beam is off.

 

Yep, sounds like a fault.

 

The thing is I don't drive in dark often enough to know how frequent this problem occurs. I does not occur every time I use Automatic High Beam, and I don't know what triggers this problem.

 

Driving around town, I can have it on Auto High Beam and it only occasionally comes on, more in back-streets. The when I turn into my driveway, they go to High Beam - but as I enter my garage, they turn to Low again - I've always suspected because of the reflected light off the back wall.

But on a country drive, it'll usually work as I'd like, though occasionally turning off for a bright road-sign, or a well-lit intersection.

Where it doesn't work well is going down a tight mountain road - it won't go to high quick enough, leaving me in the dark with another bend coming up. But if I turn the AUTO button near my knee OFF, they'll work fine manually.

 

I think auto high beam is set to low beam at low speed. That might be the main reason it is turning to LOW as you enter your garage.

Yes, it does work well enough on country road at night with a few cars in ahead of you. I usually keeps Auto High Beam switch by the knee ON all the time, and engage it with high beam switch on light lever (push) as needed at night. I don't keep the light switch in high beam position all the time.

 

Yes, around town I usually have the AUTO "ON", but the lever back in normal position.

You're right - they only operate over a certain speed - they say 30km/hr, but I think it's actually lower than that.

 

I have the exact same problem.

Sometimes when driving at night (headlights properly engaged and auto high beam on, icon illuminated on dash) after passing a car the high beams turn off(normal) but then they don't come back on and the icon for auto high beam actually turns off on the dash. Flipping the high beam stick back and forth doesn't re engage the auto high beam, the icon on dash does not come back on. The high beams manually come on when pulled towards me.(same as the other user in this thread).

If I pull the stick back and turn off the high beams and wait a few minutes, when I engage them after that it will seem to work again. On rides where the auto high beam turns off and the icon goes away it seems like it will do it frequently on that drive. Other rides it works perfectly the entire time.

This issue isn't user error, and it is not an issue with the actual high beams. Something is causing the feature itself to disable and the icon to turn off. If you pull the stick they come on and if you turn off the auto high beam feature using the button by your knee they come on, but if you press the button again the high beams turn off and the icon in the dash for 'auto high beam' doesn't light up.


This is separate from the 30kmh speed limit. Even if you are going 1kmh the auto high beam light on the dash is still illuminated if enabled, even if the high beams themselves aren't turned on due to too slow speed. In this case the light goes off and the high beams will never come on again unless the stick is flipped off and several minutes pass before turning back on.

I have even experimented by sitting perfectly still with auto high beam on(actual high beams off obviously). Eventually a car will drive past and the auto high beam feature will disable and the icon goes out on the dash. Even sitting there for 15 minutes the auto high beam icon won't come back on unless I pull the stick and wait several minutes before putting it back.

 

Yap, you are correct. I am sure with many people having the same symptom, this is some hardware malfunction. I can see there is going to be recall on this soon. I have 20K scheduled maintenance appointment with my dealer tomorrow. I will update what they say. My feeling though is that they don't have solution yet.

 

Isn't the sensor for this in the toyota emblem near the front middle of the car? Should have nothing to do with the windshield. Have you tried cleaning the emblem?

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