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Headlights and brake lights

I have a 2000 Hyundai Sonata. With the headlights turned off, they come on when I brake. How do I correct this?

That’s pretty weird. Does this car have the DRL (Daylight Running Lights) or maybe some sort of automated lighting feature, where the lights automatically turn on when it gets dark?
Does this happen with the key out of the ignition while stepping on the brake?
Does your license plate light go on when you hit the brake?

One more question…Where is the headlight switch located? On the turn signal stalk by chance?

I have a 2000 Hyundai Sonata. With the headlights turned off, they come on when I brake. How do I correct this? The dashboard lights and the licence plate also come on whether the ignition is turned on or off and no matter whether the key is in the ignition. The light switch is on the turn signal stalk. There is no automated lighting feather.
CJ43015

Just to state the obvious, you’ve got to have a couple wires melted together somewhere. The hot wire from the brake light has to be feeding into the hot wire for the lights and bypassing the switch to turn them on. I really don’t think it is the stalk. You’re probably going to have to take it in to an electrical shop where they can trace the wires. You can look yourself for any obvious problems but a wiring schematic and the wire routing pictures that you would get in the factory manual would be quite helpful.

Now a couple stories: Way back I had my folks 61 Mercury and when I put the turn signal on, all four lights would flash. I took it to two different shops and one guy had the steering wheel off and couldn’t find anything. Finally I crawled under the car and found the wires over the rear resonator melted together. Then I remembered the night before I had hit a rock or something on the highway and punched a hole in it.

Fast forward to about 1980 and I had a Buick station wagon that I was trying to sell. The tail lights would blow a fuse after about ten minutes of driving it. Couldn’t figure it out and police had already warned me once, until I crawled under it again and found the wires over the tail pipe had dropped down on the pipe. When the pipe heated up enough, it would melt the insulation enough to short out, then be ok again when it cooled down.

For weird stuff like this, I’d take a good look at the wire routings for anything melted, smashed in the trunk, etc.

Check to see if the rear brake lights have a double filament in them. Sometimes the brake fliament gets tied to the running light filament inside one of the bulbs and it crosses the circuits over. This normally just effects the dash lights and not the headlights but it depends how your vehicle is wired. If removing the brake light bulbs clears the trouble then one of them is crossed internally. You usually can visually see the filaments touching each other inside the bad bulb.

That’s a tricky problem.
He didn’t mention that the lights are turned on and said it doesn’t have an automated light feature so that shorted bulb signal would need to cross over to relays that are open. If the bulb was shorted, it would just turn on all tail lights. There’s no path from the tail lights to the head lights, except through some relays that are both open when it is day light.

I asked about the tail light/plate light because that’s steered through a separate relay from the head light relay. According to the schematic I dug up, they are both controlled through a double pole switch on the tree. Just having that switch shorted or any of its wires wouldn’t do what’s described.
You would have to have not just one but at least two shorts for the headlight/taillight to come on when you hit the brakes.

Not only that, but the brake lights would also need to come on when you turn on the headlight when you turn on the switch on the tree.
Is that happening as well?

Edit: After looking at that schematic some more, are you absolutely sure you don’t have DRL? Do you maybe have DRL but is it disabled? Does your dash backlight go on when you press the brake?
There’s an explanation with DRL but without it your system will need to be shorted in several places…