Question on Automatic Headlamps

[PJayUK]

Hi all

A hopefully quick question on something that is annoying me!

I have been fiddling with the headlight settings on my MY2000 W220 S320. I have three settings Automatic, Manual & Constant. I also have Xenon's on my car.

When I set the system to Automatic the Xenon headlamps fire up as soon as I switch the key to position 0 or the ignition on. This does not happen when I use the constant setting, in this mode the Xenon headlamps dont come on until the engine is started.

This is annoying and not what I am used to in other cars with Auto headlamps. As a consequence of my job I spend a bit of time in the car with the radio etc on but the engine off, and it seems a real waste of energy and bulb life to have the full dipped headlamps and all the running lights burning away. I would have expected the Xenon's headlamps to only come on when the engine is on or at least the ignition.

Am I missing a setting somewhere? the manual has not helped clarify this very much!

Can anyone shed any light (excuse the pun!)

 

[television]

Surely if you set them to manual, that would solve it, in the convenience menu there could be a menu for light on when exiting the car, you can also turn that feature off

 

[PJayUK]

Your absolutely right, I have set them to manual, but I really like the Automatic feature. Its one of those things that I find really annoying because I must be missing something a setting or configuration must be wrong! But perhaps not, maybe the headlights are meant to be on when the engine is off in this mode or perhaps its something that a dealer can change with STAR?

Either way this has sparked my thirst for knowledge and now I want to find out more!!! And confirm that there is not a problem somewhere!

Damn I must see a shrink about my automotive OCD tendencies!

 

[whitenemesis]

Hi all

A hopefully quick question on something that is annoying me!

I have been fiddling with the headlight settings on my MY2000 W220 S320. I have three settings Automatic, Manual & Constant. I also have Xenon's on my car.

When I set the system to Automatic the Xenon headlamps fire up as soon as I switch the key to position 0 or the ignition on. This does not happen when I use the constant setting, in this mode the Xenon headlamps dont come on until the engine is started.

This is annoying and not what I am used to in other cars with Auto headlamps. As a consequence of my job I spend a bit of time in the car with the radio etc on but the engine off, and it seems a real waste of energy and bulb life to have the full dipped headlamps and all the running lights burning away. I would have expected the Xenon's headlamps to only come on when the engine is on or at least the ignition.

Am I missing a setting somewhere? the manual has not helped clarify this very much!

Can anyone shed any light (excuse the pun!)

Just a couple of points requiring clarification...

You say the xenons come on with key in position 0 or the ignition on, then you say you would have expected the xenons to come on only when the engine is on or at least the ignition??

If your worry is sitting in the car listening to the radio with the engine off, just turn the ignition to 0 or even take the key out. The radio will still function (for up to 30min).

All that said, everything I have read around this subject suggests the headlights should only come on when the engine is running. Certainly that is what happens with my car (C class admittedly).

The welcome lights function only illuminates the parking and fog lamps. On switching off the ignition my headlights stay on for approx 5sec then extinguish with the fogs and parking lights taking over as the "see you home" function. They go out after approx 30sec.

Unless the S class is significantly different in it's set-up I think headlights on without the engine running is not normal.

 

[PJayUK]

Thats correct it works like this...

1 Insert key, easy entry function operates and the steering wheel moves into position.
2 Turn key to 0 Radio Position, automatic headlamps operate including all running lights and Xenon dipped headlamps.
3 Turn key to start engine, no change to exterior lighting but footwell courtesy lights go out for a second until the engine fires....

Sounds odd doesn't it. I rang a local dealer today and asked them, but there resident SClass guru wasnt in today so they are going to call me back. But surely this cant be correct operation.

Am I missing a courtesy or day running setting perhaps?

 

[whitenemesis]

If you remove the key and open the car door do you get a warning tone?

 

[delboy777]

When my lights are on AUTO they do not come on in any key position until the engine has started. When you stop the engine they go out automatically 2 seconds after the engine stops.

 

[television]

When my lights are on AUTO they do not come on in any key position until the engine has started. When you stop the engine they go out automatically 2 seconds after the engine stops.

Thats the way the auto lights are intended to be. and thats the equivalent of running lights

 

[whitenemesis]

Surely running lights is the constant setting? Lights come on with the engine no matter what the light level is

Auto lights only come on only when the light level drops to a preset level. No lights come on when the egine has started unless it's dark enough

 

[delboy777]

Surely running lights is the constant setting? Lights come on with the engine no matter what the light level is

Auto lights only come on only when the light level drops to a preset level. No lights come on when the egine has started unless it's dark enough

Havent tried em in the daylight yet, allways been in the dark will try today and see but its a bit grim here weatherwise very overcast and dark.

 

[PJayUK]

Sorry for the delay in responding...

In answer to Whitenemesis in Post 6, no I dont get any warning tones at all. The headlamp dial is set to 0 when the lights are on Auto and they behave in the way I described in the original post. As far as them coming on only when the engine is on, well that seems to the be the problem. They fire up (xenon dipped headlamps included) as soon as the key is turned to the what the manual refers to the Radio position. The lights are not affected at all by the engine.

The constant setting operates in a more sensible way. With the Xenon's only coming on if the engine is on, and going off when its switched off. This seems the way it should work in Auto (with the ambient light controlling when they come on or go off).

All seems very strange to me, I accept that the W220 might be a bit different to other models but this just seems plain stupid!

 

[television]

I have checked in the workshop info, and nothing listed for this shown.

If you did not have the car from new, could it be that day time running lamp have been fitted, that would do this

 

[PJayUK]

Television thank you for a very interesting post. Is there any way I can find out if this option is fitted to my car?

Also I am not familiar with this feature and my manual doesn't appear to reference it, would you be able to explain what it is and how it works?

Oh and finally, can I override or disable this feature?

Thank you I feel likeI am getting somewhere now!

 

[whitenemesis]

According to WIS the way in which the lights are set changed with my'06.

There is a setting in the cluster menu that will set/un-set the lights to constant. post '06

Slightly more restricted settings pos on pre '06 cars. Either way PJay, the headlights lights shouldn't come on until the engine starts.

Even with a duff sensor and my car thinking it was permanent night, the dipped beam only came on with the engine running!

 

[television]

I have been doing some more reading on this, and checked my own car that has the same system.

The driving lamps, as they are called should come on if the rotary switch is set to "auto" but not if set to off.

If the lights are coming on when the rotary light switch is set to off, then there is a fault in the overhead control panel, this contains the sensor along with the auto wipe function

 

[PJayUK]

My rotary switch does not have an auto setting. The only auto setting is in the cluster menu on the dash....

Can the daytime running light settings be disabled by a dealer on star?

 

[television]

My rotary switch does not have an auto setting. The only auto setting is in the cluster menu on the dash....

Can the daytime running light settings be disabled by a dealer on star?

Maybe I was looking at a slightly newer version that does have the switch, as these things are SAM controlled, then I would say yes and that they can be turned off, daytime running lights would come on with the ignition

 

[PJayUK]

Is it something I can do myself or is a trip to the dealers in order?

 

[PJayUK]

The manual say the following...

"The headlamps can be switched on and off manually or automatically or switched to daytime driving mode"

"Automatic Operation, turn the electronic key to position 0 in the starter switch, the sidelights switch on and off automatically depending on the brightness of the ambient light. Turn the key to position 1 in the starter switch, dipped beam headlights, side lights and license plate illumination are switched on and off automatically. The dipped beam headlamps can still be switched off and on manually using the light switch"

So am I missing some key operation with the light switch here??

It goes on to say....

"Daytime driving mode, turn the light switch to position 0. The dipped beam headlamps sidelights and license plate illumination are switched on when teh engine is running, you will only be able to operate the headlamp flash and not the main beam headlamps. The lamps will be switched on according to the position of the switch, if you move the light switch from position zero."

Now I don't consider myself a stupid person, but this makes little or no sense to me. It doesn't explain what daytime driving mode is and how it is any different from normal automatic operation. It implies however that unless you want daytime driving mode the switch should not be left at position zero.

I have just spent the last hour fiddling and it still makes no sense!

Any ideas?

 

[PJayUK]

And I have just found out that the headlamp dial switch works even if the keys are not in the ignition at all. I can unlock the car and switch the headlamps on via the switch without even putting the keys in...