If the stalk is on AUTO, it's pretty dark before the headlights come on. Has anybody found a way to make the sensor more sensitive to darkness?

 

unfortunately i havent seen an option to adjust the sensitivity

 

Where is the light sensor located? Maybe adding a layer or two of scotch tape would make the sensor more prone to sense darkness?

 

The light sensor is incorporated in the rain/light sensor located on the inside of the windshield, below the rear view mirror under the plastic cover. It measures the ambient light around the vehicle in a vertical direction and also the angular light level from the front of the vehicle.

The automatic headlamp operation uses ambient light levels which are monitored by photodiode incorporated in the rain/light sensor. According to TOPIx they are activated under the following conditions:

1. Twilight
2. Darkness
3. Rain
4. Snow
5. Tunnels
6. Underground car parks.

I also note that mine come on during very bright sunlight as well, such as driving towards a low winter sun.

There does not appear to be any diagnostic instructions for the auto lamps triggering late/early. Modifying the light getting to the sensor will likely affect the auto wiper function as well as they share the sensor. IIRC (and I may not be) the rain sensor uses the internal reflection of IR light within the glass to determine if water is sitting on it. If that is correct you may be able to cover/darken the sensor on the outside of the car without affecting the wiper sensing. I guess it depends how local to the IR sensor the water droplets need to be to be sensed. The light sensor is visible from outside the car by looking at the blacked out section under the mirror mount. You could try putting a bit of window tint film over that area to see if it changes?

 

I guess a bit of tinted tape over the sensor might make the lights come on earlier?

 

Getting scraps of window tint from a tint shop is easy to do. The patch has 4 diamonds, and two lighter sensors on each side. Is there any part of the patch that shouldn't be covered, or can I cover the whole thing? It will certainly look more correct if I can cover the whole patch.