offroad200

I recently spoke with the Diagnostic Specialist at the local Lexus Dealership. He had a customer with the same issue and took the problem all the way to the engineers. It does operate differently than the 2010. The green indicator goes off when the parameters aren't there for it to operate, i.e. speed, external light, etc. The system is still on and operating and will turn the green light back on when the proper parameters are established. We both agreed that this was kinda stupid. The parking assist light stays on even if you aren't using them. But not the auto high beam. There's not much that can be done at the dealership level.

satnav

Thanks I agree I think its even more dumb how the RCTA, and some other safety acronym in the right side of the intrusment cluster and park assist stay on all the time. It really should be the opposite when its off or malfunctioning.

bdman360

Just curious, whats the purpose for "auto high beam"?

kitlz

The auto high beams help when driving on dark roads. They'll come on automatically but switch to low beam when a car approaches from the other direction.

Supranut

I turn my auto high-beams off the other day to watch some deer going across my yard since I was stopped I could not put the highbeams on with it activated, then I forgot to turn it back on. While driving down the road the next day, I was trying to turn the auto high-beams back on and it would not turn on. I tried both with the high-beams off and with them on and while I was moving it would not activate. When I got to a stop sign I turned off the high-beams activated the button and it came on, then after that it worked fine. I'm not quite sure why they would only come back on only when I was stopped.

satnav

interesting since getting my front windshield replaced the auto high beam has been working flawlessly!!! The green Auto symbol is always their now.

tkspeedy5

My 2016 RX350 just started having this problem after a year and a half where the "auto" icon comes on and off at random. When "on" the lights work perfectly. When the auto icon goes off it is as if this capability doesn't exist. Pressing the auto high beam button does nothing. Rotating the light switch of "auto" and back to "auto" des nothing. The icon just comes and goes at random. Any fixes known?

offroad200

When the auto light goes out, does the system still work? AHB isn't like other systems such as when Park Assist is on there's an indicator light for it. The AHB light doesn't always stay on even though the feature is active. When the indicator light is off it's saying the conditions aren't right for AHB to work. Like in a well lit neighborhood for instance where you don't need high beams.

tkspeedy5

Thanks for the quick reply. When the button is push on the dash to enable the auto high beam AND the light setting is set to auto AND the multi function stick is pushed away to enable the high beams, the green "auto" icon in the speedometer comes on. it is supposed to STAY ON and it did so for 14 months. Then on November 2nd the green auto icon started going off and on for no apparent reason. When it is on the high beams go on and off correctly depending on ambient lighting conditions. When the green auto icon on the speedometer disappears (goes off) it is as if the car had NO INTELLIGENT HIGH BEAM SYSTEM AT ALL.
The only solution is to disable the auto high beam system either with the switch on the dash or move the light switch on the column off the auto setting on on the headlights and activate the high beams as needed manually. I did not pay this much money to have one of the convenient safety features of the car stop working after 14 months.
The problem is NOT in the dash switch. If you disable the option and the column switch is pushed away the high beams always come on as at this point the have been manually enable. The car "knows" the intelligent high beam system is enabled when the dash switch is depressed. I believe the problem is in the switch in the column which "forgets" that the system is enabled periodically and randomly at unpredictable intervals. Is it hardware (the column switch) or a malfunctioning chip or motherboard in the car? That is most probable to me. I don't think it is a software problem.

I emphasize that the auto green icon on the speedometer should be on ALL THE TIME, and it was at night for 14 straight month. When it is on the AHB works perfectly when it goes off it is if the AHB doesn't exist.

Thanks again for your comeback. By the way there is a whole thread in the Club Lexus site under the heading "AUTO HIGH BEAM DISAPPEARS". The manifestation of the problem as experienced by others exactly the same as I have experienced. The problem is widespread and I am getting little satisfaction from the dealer.

Best regards

mikemu30

great feature when driving in rural areas.

guxu

I saw the same thing the day before yesterday. But I did not do anything and after a while the icon came back.

Rarebird

thanks for posting this! I’ve wondered myself why the green icon on the dash would appear and disappear completely randomly, now I know.

ihateduke

Same here! It's really bizarre and I can't figure out a pattern besides it's happening more often now. My guess is that they will issue a bulletin on it at some point.

tkspeedy5

Problem solved REALLY SOLVED

tkspeedy5

In November my 2016 RX350 started having the problem with the green auto icon disappearing from the center of the instrument cluster effectively disabling the auto high beam feature.

Conditions needed to enable auto high beams

• Auto button in lower left corner of the dash must be pushed in
• Headlight switch set to "Auto"
• Multi function arm attached to the left side of the steering column must be pushed away to "turn on" high beams
• Speed must be about 25 MPH or higher
• Necessary ambient light conditions must be detected by windshield camera to turn on the high beams

Problem

• At random intervals the auto icon in the speedometer area would go off and the auto high beams ceased functioning
• Icon would stay off for seconds to minutes and then come back on and the light again functioned correctly
• Icon would again disappear disabling the auto high beam capability

Work around

• Disable the auto high beam system and turn high beams on and off manually
• UNSATISFACTORY

Cause

• Apparently on a very small percentage of cars with the auto high beam capability a film can develop on the inside of the windshield between the camera lens which is housed in a sealed box on the back of the rear view mirror, the camera obviously facing forward
• No one in our car smokes, the cause of the film is unknown
• Cleaning off the outside of the windshield at the top does not alleviate the problem as the film is on the inside of the windshield and on the camera lens
• The film was distorting what the camera was observing and it made repeated attempts in a very short time (I'm assuming nano seconds) to determine if the high beams should be on or off
• All the other criteria for having high beams working were in effect, it was an ambient light situation
• The techs at Lexus in Texas surmised that there is an algorithm that would disable the system (turn the icon on the dash off) to protect it it got confused as to whether the high beam should be on or off

Solution

• Dismount the ambient light camera located behind the mirror
• Clean the camera lens
• Clean the INSIDE of the top of the windshield through which the camera looks
• Re calibrate the camera

Result

• The dealer in Augusta GA put the car through its paces over 3 or 4 nights and reported that the system was now working correctly
• I picked up the car and took it on a 25 mile drive through small towns and dark two lane country roads in South Carolina tonight
• Works perfectly as designed
• I am happy

Hope this helps anyone with the same problem. Let me know
I'm out......