Dextrator

Hey guys
I had this problem for a while now, couldn't figure what it means or how to fix it - and only now did I come to the conclussion to ask for help.
One day my car alarm went nonstop for 12+ hours, draining every ounce of battery in it.
Once I recharged it, I noticed something weird with the lights.
If I DO NOT turn the lights on (leave them as it is) they are automatically on as I start the car,
But once I turn the buttons for the lights - they go off (lights are OFF outside-despite me turning them on from the drivers wheel)...
Its a bit hard to understand but let me know if you cant get it, I will try to rewrite this better...

Anyway, its been like this for a couple of months I did not mind, but last couple of nights I noticed my backlights remained on no matter what I was doing.
Long story short- i forgot to figure this out and now my car is dead... drained completely whereas even plugging in the key does not get any reaction, and using my keyfob to unlock the car also doesn't work. Not even the clock on the radio shows up.

Wanted to see different opinions, what is the cheapest way for me to try to figure this out myself?
I was thinking recharge the battery but I need recommendations/suggestions for something powerful that goes into a wall or is portable.
I think this will need a couple of hours to charge due to me being unable to turn off the lights now - as they are permanently on when I tried to jumpstart it with another car, it couldnt charge because all of the electricty was going into the lights.

Tomtwtwtw

I'd say grab a portable jump-starter off Amazon or where ever. It should be able to supply enough juice for even the deadest batteries, and once you're running the alternator should take care of the rest unless your battery has some kind of actual short in it. Plus you can just store it in your center console in case you get stranded somewhere.

Dextrator

Just bought a charger, charged the battery completely (took abt 8 hrs) returned it to the car, my brake lights are on but my car has 0 electricity in it... I don't know how the lights are on but i cant even unlock the door with the key fob, the radio clock doesn't even show up and nothing when i put the key in the ignition - all while the light is still on.
Any tips?

Tomtwtwtw

Very weird situation for sure. At this point I would start checking the fuses and relays, though I have no idea if that's the actual issue. Electrical gremlins can be very difficult to track down.

Chopperpilot

Just to be sure you do not have an aftermarket alarm system , right ? There’s many a post with factory hood latch/switch causing unwanted alarm activation too.
The alarm system uses the emergency flasher to work stop lamps and turn signals . Perhaps there’s just enough juice to power brake lights at the end .I dunno.

Although it’s a pita Some have disconnected the hood latch switch with success , will definitely stop the unwanted midnight blast too ! Hope this helps..

Dextrator

Not sure but it could be, i bought the car second hand so anything is possible.
But this time it didnt go off with an alarm, the thing that drained the battery was just the brake lights that are on.

MtnRDX

My kid found the button press combination to undo the keyfob from the car. But I was still able to start it and I didn't have a dead battery in the mix.

I'd check that and also hook up some jumper cables to a known good battery and see if you get any reaction to inserting the key then.

If nothing is happening then you'll have to check fuses and stuff.

Sounds like you could have a bad light switch or relay or a short somewhere. I would pull out the related fuses and relays for the lights and DRL and see if you can get it started.

Then while it is running make sure your alternator is charging by checking the voltage at the battery, Then reinstall the fuses, and swap the relay to another position to see if it causes an always on situation on that circuit. I don't remember but if it is the same as the condenser (A/C) fan relay you could put it there and see if the fan runs with AC on and doesnt with AC off. If it stays on period then yeah you know. But sometimes they will work proper for a bit and you can't be sure. So having a good new spare for the common ones is good. But if you swap in a known good relay to the troubled lighting circuit the issue should resolve if it is a relay stuck.

I had this happen to me, but it happened to be a fan relay. I shut off the car, took the keys out, went to walk off and realized my fan was running still with no keys in the car.

Dextrator

Thanks for the suggestion but I think this is something different.

The car is completely dead somehow except the brake lights.
I just ordered new brake light switch gonna try to replace it because I heard that might solve the reason why theyre permanently on.
As for the fuses, I tried checking them but because the car is dead I was not able to get any reaction.
I will post here if changing the brake light fixes it.

UPDATE: I Bought new car battery but still the car is dead, and the brake lights are on.

MtnRDX

OK so when you say the car is dead still with the new battery, what does that mean.

Nothing works but the brake lights? No interior lights? Headlights? Wipers?

Nothing happens when you open the door, insert the keys, try to start....

Does the little blue ring around the key illuminate? If you turn the key to ACC does anything work?

Trying to figure out if it is possibly a key security situation or something shorted/fried/blown... like something in the under hood fuse box, or body control module, or computer... or if it's the key security system not recognizing or reading the security chip from the key... thinks it's been stolen.

Had the security key situation with my jeep is why I'm asking.

Dextrator

Hey
Yes that is right, when I say its dead there is literally nothing going on in the car that indicated any power whatsoever.
I just replaced the brake light switch, it fixed the problem and my car no longer has permanently turned on brakes.
However, even after a new battery the car won't start. For a millisecond, lights popped up on the dash when putting the key, but when I tried it again nothing.
There is no blue circle when you put the key, nothing happens when u put the key or turn it.
I doubt its stolen key I think the power was just drained but now some electricity problems occured. Any ideas what it can be?