You will probably have to manually switch between day and night mode if you disconnect the sensor. Isn't that what you are trying to avoid?

 

I give up,
later,rethinking the system,the sensor is usually a light variable resistor and changes from hi to low resistance with light changes. if its low in daylight then it goes high in darkness or vice versa..
if low in light and you pull it the bcm sees high like its dark! lights on! you may need to short it,(make low)
if its high in light , it will stay high when pulled, lights out.
we don't know how the software responds as you said it resets.
you can only try some things once its out.

 

You may be right.
I was hoping to leave the nav. head unit in night mode and day mode and it would still sense when lights were on manually

Lights on night mode
lights off day mode

Of course now you have me concerned that this might be a futile exercise, all together
I have wiring diagram for the vehicle and the sensor does look like it has more to do than I expect.

I will report back to all of you, after I try this . . .

 

-UPDATE-

I have unplugged the ambient light sensor and the headlights are behaving the way I wanted.
I do have to rotate the headlight switch to the left each time I start my 3, but that is a small effort.
The ambient light sensor is a photovoltaic sensor, that keep the voltage to the BCM at between 1.75 volts and 4.9 volts.
If anyone else is interested in this procedure, the sensor comes out of the dash from the top.
Just use a small trim tool and it pops right out. There are two wires attached (Blk & Wh)
Unplug them and use a string to tie them to the sensor, just to hold them and keep them from falling back into the dash. Then snap the sensor back into the hole and you're good.

Call me crazy, but this all works for me.

 

great!,good info, I just might do it too.

ilike to be able o kill all lights when I want to.

 

I made the sensor eye a little more dark with a felt tip to make the lights go on a little earlier so I have lights on at alleys or early evening.