Usually in the driving handbook, it tells you. Please correct me if I am wrong. I believe that headlights are turned on in the early hours of the morning and at dusk time (late afternoons and evenings)
Headlights might stay on in a Honda Odyssey after the engine is turned off because of a courtesy timer. The headlights will stay on for a few seconds after exiting the vehicle so the driver can go into a building at night safely. If the headlights are staying on all the time, check the timer for this feature.
Did they used to go off with the ignition? On most cars, the headlights will come on at any time by just turning them on. The car does not need to be running or the key turned on.
the courteous time to dim your headlights is as soon as you see another vehicle, or within one half mile.
Headlights should not be left on while the vehicle is not in use. If you are not driving, you will just drain your battery while having your headlights on.
If you can see the oncoming vehicle then he can see you. Dim your lights at that time.
Your headlights need to be adjusted, you do this by popping your hood and adjusting them by the screws on the top or bottom of the headlight, most of the time you will need a screwdriver to do this.
you must use your headlights between one-half hour after sunset to one-half hour before sunrise, or anytime when person or vehicles cannot be seen
500
you can have your car lights on at any time but you do not have to have them on
1000 feet
The first headlights on cars were invented in the 1880's and were configured similar to gas lamps of the same time period. The first electric headlight was invented by the Electric Vehicle Company.