Headlights staying On

It could be driving lights mode instead of low beam. Check connections.

depressing the lever just turns on high beam momentarily. Keep on depressing until to you hear the switch "clicked" in to turn on and stay on. "De-clicking will turn it off.

Do you have power in and out of the dimmer switch in the low beam position ?

Sounds like it's in the actuator itself - the part that you move on the steering wheel or dash to put the high beams on or the headlight switch itself.. Find the ground wire on the headlights and run a new wire from that directly to the body somewhere so it gets a good ground, or directly to the neg side of the battery.

If you have separate bulbs for the low and high beams(4 light system), if you pull the turn signal and hold it, all 4 lights will stay on until you release the turn signal. You need to replace the bright bulb on the right side and the low bulb on the left side. If your headlights only have one bulb on each side, then you will have to replace both of them to get everything to work.

it sounds like a bad light switch

check the parking lights fuse

with a test light ground connected to the positive battery terminal,,the one that will light up the light is the ground...the other 2 wires are the low and high beam. cut one of those,if the low beam is now on,you cut the high beam wire. if the high beam stays on,you cut the low beam wire.

Check Hi beam bulbs they may both be burnt out, and check both fuse boxes. Headlights are offen on separate fuses Left/right so you don't end up with no lights at all

If both your low beams are not working your headlights went out and need to be replaced.