Automatic High Beams Not Functioning?

I don't know for sure, but I think Forward Camera mounted on high up on the windshield must to be a part of sensor. It is looking for a oncoming head light, I don't think it is using radar used for DRCC. In any case, even if the radar behind the emblem is involved in sensing the oncoming car, it makes no sense it turn off and back on by it self as I experienced today. Also, I get no warning what so ever including one for pre-collision system which happens often enough when the emblem become occluded.

I am at Toyota dealer right now for my PRIME's 20K maintenance. I mentioned about this Auto High Beam problem, and a tech said he will look into it. Although since it it difficult to reproduce the problem in a shop, in absence of Toyota Technical Bulletin, he may not be able to do anything for now. At the least, formal report will go into the record.

 

If anything I think this is a software issue. Something is telling the computer to temporarily disable the auto high beam feature for some reason.

 

Brought up the auto high beam problem to the dealer service when I had 20K service appo. They checked code, found nothing. Looked for Technical Bulletin, found nothing. It was daytime so they could not reproduce the problem. It was on Saturday so they could not call Toyota Technical assistance for advice. Therefore, no remedy found. I will likely have to contact Toyota myself to find out what can be done.

 

Hello,
I've got the same problem with my 2016 Prius Touring 3. I don't drive at night very often, but last night I noticed that high beam indicator was on on the dashboard, but the high beams were not going on and off. They clicked on once when i went around a turn, but other than that, the high beam does not automatically go on or off, despite the dash light being on. Has there been any updates? thanks!

 

No, as I commented, Toyota says this is the way it supposed to work. Very smart engineers at Toyota thought this through and intentionally made the "Automatic" high beam to behave like this. Go figure.

 

What speed were you driving? Is your windscreen (and Dashboard) clean?

This is a Gen 4 thread - you might ask it on the PRIME Forum - they might have different issues relative to yours.

 

hmm, that is odd. I could have sworn that they were functioning differently before, but I'll have to continue to monitor. It is amazing to me that I've gotten used to auto-everything, and now find it inconvenient to raise and lower the high beams manually!

 

I was driving around 55-60, but it was on a 2 lane road, that potentially it could perceive oncoming cars closer than they are - I could've sworn it working differently before. When you ask if the 'windscreen is clean" - I'm not sure what that is? The windshield is clean though, and they cruise control is working fine - doesn't is use the same technology for that as the auto high beams? thx!

 

It uses the Forward Recognition Camera - behind the Rear Vision Mirror for Auto High Beam.



I suspect it DOESN'T affect Auto high beam - but the system also uses the Headlight Sensor Control at the bottom middle of the dashboard next to the windscreen to turn Auto Headlights on/off. I was amazed at how dusty it can get town there - almost out of reach - - but worth checking anyway.

 

thank you for that - I will check. Is it possible that even when my auto headlights go on at dusk (sensor sees it's getting dark), that the high beams only function when it's much darker out? If that true, that may be that their is communication between the two sensors you noted?

 

The auto high beams only function when it is significantly dark. If you have the auto high beam light on on the dash, then the high beams should come on if it is dark enough. When the high beams are actually on you get both the auto high beam light and the blue high beam light.

Is the auto high beam function by your left knee turned on?

The original problem here was the opposite, the high beams go off, and the auto high beam light goes off, even though it is enabled by the knee.

 

Anybody know how to disable the system? I am having the same problems with my generation 4 but can't get that button by my left knee to turn off.

Nexus 7 ?

 

No - as far as I know, the button near your driver's door knee should work. If it doesn't work, it needs repair.

 

Let us know what you find out when you talk to your dealer. As I commented in #24 I had the same problem, and I brought it up all the way to Toyota HQ, but the answer they gave me was that is "the normal functioning" of the system. I have turned off the auto high beam for now.

 

Has PRIUS c got the same system - I thought the technology was different?

 

I eventually got the button to turn off but I certainly won't be turning it on again!

Nexus 7 ?

 

I am experiencing the same problems exhibited by other users in this thread. Headlights on, auto high beams on, auto high beams will appropriately dim and auto high beams system will intermittently deactivate (evidenced by the automatic high beam indicator on the dash turning off while power is on for the system via the button near my left knee). I worked this issue up via Toyota customer assistance. The vehicle was with the dealership for about 2 weeks. The service manager duplicated the problem on my vehicle and a "like model" 2019 Prius from the inventory. Toyota customer service and the service department's technical assistance both have deemed this to be normal operation. As this is a safety issue. I have filed a complaint with NHTSA and encourage others experiencing the issue to do the same. This is clearly a larger problem that Toyita is refusing to escalate and address.

 

Yap. I got the same answer from Toyota HQ. I no longer use the auto high beam. It was marginally useful to begin with. I'm not missing much.