Automatic High beams fail in overcast/rain

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2017 CX-5 GT AWD
My Automatic high beams work great at night - switch off when ever a car approaches, or I approach a car, and in some other situations that are apparently automatic.

But today it is raining and overcast. My auto headlights came on a few times, and with them my high beams - the high beams would not go off on their own. I guess the camera could not easily detect headlights and tail lights from other cars.

Does anyone know if there is any tuning of this system? The easy solution is to turn off the high beams completely, which i did. I haven't seen other mention of this before, and wondering if others have noticed it. I am surprised the light sensor (and camera and cpu) that turns on the auto headlights doesn't have enough sensitivity to differentiate dusk/overcast from night.
 
Make sure your defroster is working?

It’s often foggy this time of year in Germany and I haven’t noticed a big problem. Yes the range is diminished but not hugely, at least in my case.
 
In certain situations it’s best to just go manual mode. These systems do not perform as planned in some cases and the owners manual makes note of that as well.
 
Defroster? Windows were not obscured from humidity if that is what you mean. There was no condensation of any kind on the windows and detection of headlights and tail lights failed even when on top of another car.

I guess it is just something to be aware of - not working in certain conditions.
 
Just dip back the high beams lever to normal and remember to dip them after the event has passed.

Problem solved!
 
This was my first rain day, when auto headlights came on, the high beams would come on and stay on. The auto headlights came on for about half of my driving, and during those times, i had to shut off the auto high beams or they would stay on. The sensor(s) would not detect anything that would shut off the high beams. Maybe there was one instance where the high beams shut off and headlights stayed on, I am not sure. But at least 99% of the time, the high beams stayed on with cars in front of me or coming towards me with headlights on.

So I had to turn off Auto High Beam; or else when the headlights came on, they would come on with high beams and not go to low beams, annoying other drivers.
 
The auto- high and low beam feature has some difficulty in dense fog as I have also noticed. The switching is not always accurate since the camera has difficulty in seeing the light from opposing vehicle in fog. It may stay on in high beam (causing the traffic on the opposite side to flash you) or stay on in low beam. Actually with dense fog it is best to stay on in low beam. That way you do not have your own beam of light being reflected back to you causing more blindness. Keep low beam and drive slowly.
 
It is normal for auto lights to come on in inclement weather.

Yes, they appear to be using a light sensor to activate (amount of daylight) not the fact that wipers are going, or any other weather phenomenon.

I am not disagreeing with the lights coming on, just the lack of proper behavior with Auto High beams.

If I were programming the system, I would have either better light sensor, or multiple with different characteristics. The system should be able to say:

1. It is getting dark enough to enable headlights
2. It is not dark enough to use auto high beams, keep high beams off as they show no value.


I get that the camera is probably what catches headlights and tail lights, and because it is daylight out, it can't "see" either, and so high beams stay on. I am just surprised Mazda didn't put a little more into this part of automation.

The manual lays out certain conditions for HBC - but I think Mazda engineers overlooked a simple cloudy day use case:

The system switches the headlights to low beams when one of the following occurs:  
 The system detects a vehicle or the headlights/lights of a vehicle approaching in the opposite direction.  
 The vehicle is driven on roads lined with streetlamps or on roads in well-lit cities and towns.  
 The vehicle is driven at less than about 20 km/h (12 mph).

I was at 1 mph rolling to a stop light and hi beams were still on.

Ah but wait, as i read further, it does say they are working as designed:

NOTE The timing in which the system switches the headlights changes under the following conditions. If the system does not switch the headlights appropriately, manually switch between high and low beams according to the visibility as well as road and traffi c conditions.  
 When there are sources of light in the area such as street lamps, illuminated signboards, and traffi c signals.  
 When there are refl ective objects in the surrounding area such as refl ective plates and signs.  
 When visibility is reduced under rain, snow and foggy conditions.  
 When driving on roads with sharp turn or hilly terrain.  
 When the headlights/rear lamps of vehicles in front of you or in the opposite lane are dim or not illuminated.  
 When there is suffi cient darkness such as at dawn or dusk.  
 When the luggage compartment is loaded with heavy objects or the rear passenger seats are occupied.  
 When visibility is reduced due to a vehicle in front of you spraying water from its tires onto your windshield.

So moral of the story.... RTM and when you think you read it, read it again.
 
Correct me if I am wrong but the headlights come on automatically when the wipers are activated.

The manual makes it very clear that all the tech like auto wipers, high beam control, radar cruise control and etc may experience situations or conditions that the systems can not decipher. The technology is still in its working stage. For example, the car might not stop automatically if headed towards a picket fence.

In the end, the driver should be in command at all times and not be swayed to let the tech take away responsibility of driving.
 
@ alphadog00. Spot on comment. That’s why when I read comments here how some use cruise control in stop and go traffic I get a bit annoyed. I hope I’m not the one to get hit because “the system failed me”.
 
I read my owners manual from cover to cover when I bought my 6 and will be doing the same when I buy my CX-5
 
I read my owners manual from cover to cover when I bought my 6 and will be doing the same when I buy my CX-5

I read the manual as well but a lot of my education came from driving and experiencing things which prompted me to recheck the manual. For example, if the headlights are on auto, my fog lights won’t activate. I have to switch to manual on. So now during rain or at night I just switch to manual.
 
I have used the wipers several times in the past few months during daylight on my 2017 CX5 and the headlights have never come on when the wipers were active. I always keep them on auto. I thought that is what the manual said as well, but like Puyapim says: "These systems do not perform as planned in some cases and the owners manual makes note of that as well."
 
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