Headlight Doesn't Turn Off Automatically

[freshcar]

After the last service, the battery of my car died over the weekend. The service department replaced the battery saying the battery was low.

But I've realised that was not the real cause. I've found sometimes, ( not always), after I left the car by closing and locking the door, the headlight and tail light didn't turn off automatically ( the headlight bar was on Auto) .

I've caught this happen three times after I returned to the car in 1 hour or so after shopping.

So when this happens overnight , for sure the battery would drain.

Can anyone suggest , if this relates to sensor, or computer system of the car? thanks

[pj8708]

After the last service, the battery of my car died over the weekend. The service department replaced the battery saying the battery was low.

But I've realised that was not the real cause. I've found sometimes, ( not always), after I left the car by closing and locking the door, the headlight and tail light didn't turn off automatically ( the headlight bar was on Auto) .

I've caught this happen three times after I returned to the car in 1 hour or so after shopping.

So when this happens overnight , for sure the battery would drain.

Can anyone suggest , if this relates to sensor, or computer system of the car? thanks

My guess is that if the the headlights and tail lights are staying on all night, it would be a sensor problem. If the light switch stalk is in the Auto position, the system would be relying on the sensor to determine if they should stay on or not depending on ambient light levels.

[cduluk]

So the headlights don't go off even after time has passed after the car's been turned off??

Don't think it's the ambient light sensor... That sensor can literally be removed from the car, and the headlights will still go off after the 30 seconds or whatever passes after ignition is turned off (i've had the sensor removed in my Rx400h after doing a project involving that trim piece on the dash).

If you turn the ignition off, and hit the lock button not once, but twice- do the lights go off?

My guess is a more serious computer problem...

[pj8708]

So the headlights don't go off even after time has passed after the car's been turned off??

Don't think it's the ambient light sensor... That sensor can literally be removed from the car, and the headlights will still go off after the 30 seconds or whatever passes after ignition is turned off (i've had the sensor removed in my Rx400h after doing a project involving that trim piece on the dash).

If you turn the ignition off, and hit the lock button not once, but twice- do the lights go off?

My guess is a more serious computer problem...

Hi CD,

I see your still up too!

You mentioned the lights still going off after the 30 second delay even if the ambient sensor is removed. I wonder if this issue might be due to a malfunction of that timer routine, in that it may have some sort of glitch that is letting the lights continue to run past the 30 second window.

[cduluk]

So the headlights don't go off even after time has passed after the car's been turned off??

Don't think it's the ambient light sensor... That sensor can literally be removed from the car, and the headlights will still go off after the 30 seconds or whatever passes after ignition is turned off (i've had the sensor removed in my Rx400h after doing a project involving that trim piece on the dash).

If you turn the ignition off, and hit the lock button not once, but twice- do the lights go off?

My guess is a more serious computer problem...

Hi CD,

I see your still up too!

You mentioned the lights still going off after the 30 second delay even if the ambient sensor is removed. I wonder if this issue might be due to a malfunction of that timer routine, in that it may have some sort of glitch that is letting the lights continue to run past the 30 second window.

That's my best guess, not sure what other computers control the lights...

[SW03ES]

There are two scenarios where the lights will stay on forever and not go out:

1. If you never open and close the drivers door. The car assumes you are still in the vehicle, and leaves the lights on until you exit, then the delay counter begins.

2. If a door or the trunk is ajar.

My guess is either a door or trunk is slightly ajar, or a sensor somewhere thinks it is. Do the interior lights stay on? Does the info screen ever briefly indicate an open door when one is not open?

What happens if you lock the doors twice with the keyfob? The lights should override the timer and go out...

[freshcar]

Thanks all for the reply.

I'm thinking in the same line... there are three quiteria for the Headlight/taillights to be turned off automatically :

- the setting for the headlight is on 'Auto'

- The ignition button is turned off ( or on the Accessory mode)

- The door of the car open and closes

So I think the issue could be in the control system , not detecting either one of the above situations correctly, even thouth the action already happened.

In my situation, it may actually relate to the door. Because other than this issue, there started to be an issue with the door on the driver side. By right when the car is locked, when I put hand in the handle, the keyless entry would detect it and open the door. But recently, when I lock the car by pushing the Lock button inside the driver door, it wouldn't open the door when I pull the handle from outside. that leads me to think somewhere in the system is not sensing the condition of the door properly.

[SW03ES]

The setting doesn't have to be "Auto" even if its "On" or in parking light mode the lights will go out on their own. All Toyotas do this whether they have auto headlamps or not.

[freshcar]

To let everyone know... I brought the car to the service department of Lexus. And as I thought , the issue is related to the sensor of the door. There is one small bolt on the side of the door that was loose, and it didn't detect the right status of the door.

I believe they found the root cause.

[cduluk]

In that case, when you left the car and tried to lock it, you should have gotten that long "BEEEEEEEEEEEEEEEEEP" indicating a door was ajar.

[SW03ES]

You'd think, but maybe not if the sensor was operating sporadically...

[Freonpsandoz]

The headlights on my ES300 stay on until the battery is dead if a door or the trunk is left slightly ajar. Everybody on this forum is talking about this "feature" as though it is completely normal behavior and nobody would ever expect otherwise from a vehicle. I don't understand the purpose of leaving the headlights on forever, other than to disable vehicles and sell batteries. I have only owned older vehicles before, and I'm completely flabbergasted by this. Can this "feature" be defeated somehow? Thanks.

[1990LS400]

The headlights on my ES300 stay on until the battery is dead if a door or the trunk is left slightly ajar. Everybody on this forum is talking about this "feature" as though it is completely normal behavior and nobody would ever expect otherwise from a vehicle. I don't understand the purpose of leaving the headlights on forever, other than to disable vehicles and sell batteries. I have only owned older vehicles before, and I'm completely flabbergasted by this. Can this "feature" be defeated somehow? Thanks.

You won't have the problem if you use the switch to turn your headlights on and off manually. Or just make sure your doors and trunk lid are shut. Auto headlights are a great feature in my opinion.

[Freonpsandoz]

I think auto headlights are a great feature too, otherwise I would just turn the lights on and off manually and there would be no problem. I have another vehicle with auto headlights too; the difference is that it turns the headlights off after the selected interval even if a door is ajar. Isn't that what most drivers would want to happen? I must admit that I continue to be incredulous at the attitude that a vehicle should require the driver to pay careful attention to ensuring that all doors and trunk are securely closed and to punish any mistake in attending to this matter. Are my wife and I the only ones who are ever in a hurry to do other things? I expected that others would view this as a serious design flaw and that somebody would have found a way around it.

[1990LS400]

I must admit that I continue to be incredulous at the attitude that a vehicle should require the driver to pay careful attention to ensuring that all doors and trunk are securely closed and to punish any mistake in attending to this matter. Are my wife and I the only ones who are ever in a hurry to do other things?

I've participated (too much according to my wife) in Lexus forums for over 10 years and I cannot remember another person complaining about this feature. So, yes, you and your wife may be "special" or maybe your car has a problem that prevents its doors from closing easily.

Is the headlight off delay customizable on your car? If it is, I suggest you have the dealer set it to "Off". On my 2000 LS400, there are four choices: Off, 30 seconds, 60 seconds, 90 seconds. I have mine set to 90 seconds to provide the maximum illumination duration when parking on dark streets and in rural areas while we are walking away from the car.

[tgarippo]

I have had the same problem. occasional drained battery. I called the dealer service andthey said it could be the alternator, I dought that. There were not warnings or faults showing. and it was a couple months between incidences.

I will check the doors and trunk. The trunk does have a motorized pull-down, but maybe if there is a sensor that may be loose or bad ic could happen. if there is a sensor, does any body know where it could be?

Tony

[Danamite]

When lights are set to auto the lights stay on during the day.  Obviously they should turn off until it is dark. The headlight indicator shows up on dash.

However, they do turn off as they should when I leave the car.?????

Thanks for any help.

[punith]

But I've realised that was not the real cause. I've found sometimes, ( not always), after I left the car by closing and locking the door, the headlight and tail light didn't turn off automatically ( the headlight bar was on Auto) .  BNP Paribas Online Banking | Login

[JdefTexas]

My headlight was not turning off on my 2012 Lexus ES 350. The switch that sensed that the driver door was closed was malfunctioning.  The Lexus Tech caught it right away. $35 switch fixed the problem.