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you have left your lights on indercator

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jphnneyred

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I own a vehicle that if you turn your ignition off with your head lights on there is no buzzer or indicator to advise you your lights are on
i have limited but some electronics knowledge could some one pls assist with designing relay con-fig to pwr buzzer when lights on ignition off
 
Simple enough. Use a single pole double throw relay. Connect a wire from a headlight to a normally closed contact, and the other normally closed contact to a buzzer. Connect the coil of the relay to the "ignition on" circuit and ground the other end of the coil. Any time the engine is on, the relay is activated and holds the normally closed contacts open. Any time the lights are not on, there is no voltage to the normally closed contacts.
 
Every car I have ever owned, never had any indicator for the headlights, but could have been because I have always disabled the seatbelt alarm... My Grand Prix is the first that I haven't messed with, but has a really cool feature, automatic headlight/running lights. Headlights come on when its dark, and are 50% during the day. Before, I just made sure I had a set of jumper cables, and mostly relied on habit of checking.
 
Are/were there any standards or requirements that govern this setup? I never did understand why the lights on a vehicle are allowed to operate without the key in the ingnition. It may be some safety feature but I could never apprehend it. Maybe you lose your keys and you need the headlights to look for them? Maybe you're stuck on the tracks with no keys (how did that happen?) and need to warn off the oncoming train? Have you penetrated enemy lines and find yourself, keyless, and at some loss to signal morse to friendly submarines from an oceanside parking lot? What?

In my youth, because I was chronically mentally preoccupied (less so now), I must have had to jump start a vehicle no less than 200 times, and replace a dozen batteries due to such abuse -- because the lights remained burning when I took the key out of the ignition. Or locked the keys in the car almost as regularly (after the hide-a-key was safely deposited in the glove box from the last time I had to use it whereupon I blithely tossed it there, otherwise concentrating on how to save the world, or get laid, or both at once like in the movies).

Stationed USAF in Athens, Greece in the mid eighties I purchased a Fiat 127 hatchback. Brilliant little car. Simple, easy to work on. Holy crap.... the lights extinguish when the key is removed! The driver cannot lock his door from the outside WITHOUT USING HIS KEY!!!!!! This car was heaven sent for my type. I couldn't believe my luck. These two features saved me untold agonies over the course of two years driving it. I'm not saying this was especially clever of the Italians. Uhh, sensible? They must have looked to our vehicles and wondered at a few of these idiocies.

When I got back to the States, I purchased a little gold 1986 Honda Civic. FIRST order of business was rewiring the main fuse panel under the dash to energize the headlamp relay off of the ignition. Easy. Done. Next was to remove the driver side door panel, remove the circlip casing from the lock mechanism which retains the key tumbler pins, remove them, and toss them over the back fence into the weeds. The door still locked from inside and out, but could be opened with any key on earth. Only I knew that. No thief who tries the door handle and finds it locked is going to deduce this... he'll put a brick in the window first, like any other car. And if he's just trying to use my car to signal his comrade's subs he's just SOL.

Highly recommend all that. Sorry for the massive missive.
 
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... I never did understand why the lights on a vehicle are allowed to operate without the key in the ingnition. It may be some safety feature but I could never apprehend it...

It is not in the sense of "allowed". If lights voltage supply is fed trough the ignition switch, there can be about 260 Watts lights consumption trough the switch. That is 21 amperes making the internal keyswitch contacts to fail prematurely or in need of a much more cosly production part that can handle such current. Doing it trough an additional 30A? rated relay would also increase production costs.
 
I've long wondered about the "excessive" cost of a 30 amp ignition switch or a 30 amp relay that can be bought retail for $10...as compared to...well, if this is such an expensive item, it wouldn't be available in a Kia or a Ford...as compared to a $50,000 Lexus. Why do people keep saying, "It's too expensive, nobody will pay for quality" sitting there on a $400 easy chair or typing on a $2000 computer while their $50,000 car wishes it had a $10 relay?

And while I'm at it, why does the OP in this thread get an official "thank you" for saying his car doesn't have a "lights left on" buzzer and the people that tell how to fix it don't? Hey...The buzzer in my car doesn't work, but do I get a "thank you"? I mean...just because I jammed some electricians putty in it to shut it up doesn't mean I shouldn't be officially thanked!

Hang on...the pills are kicking in...never mind.
 
Like I said, I"m older, less prone to such distracted acts, (and surely less interesting altogether for the mellowing, but you can't have everything), so I don't leave my lights on anymore. But I don't recall the details of how I rewired the Honda back in '86. All cars have headlight relays, no? Under no rewiring circumstance would you be asking the keyswitch to handle the headlamp load on its own. The little stalk control switch on the steering column certainly isn't handling those amps so the manufacturer has included that "10 dollar relay" already somewhere. I'm pretty sure that I didn't purchase another relay for this modification when I did it. I merely reassigned the power available to the stalk switch, not to the headlamps directly. The stalk switch would not work unless the key was energized. With the key in and turned, I could operate the lights as usual. With the key removed, power was disconnected to the stalk switch and thereby disconnected to the relay (that of course honda built into the circuitry) and off go the lights. So if it was not a cost saving initiative on the manufacturer's part I'm still baffled by it.
 
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Are/were there any standards or requirements that govern this setup? I never did understand why the lights on a vehicle are allowed to operate without the key in the ingnition. It may be some safety feature but I could never apprehend it. Maybe you lose your keys and you need the headlights to look for them? Maybe you're stuck on the tracks with no keys (how did that happen?) and need to warn off the oncoming train? Have you penetrated enemy lines and find yourself, keyless, and at some loss to signal morse to friendly submarines from an oceanside parking lot? What?

In my youth, because I was chronically mentally preoccupied (less so now), I must have had to jump start a vehicle no less than 200 times, and replace a dozen batteries due to such abuse -- because the lights remained burning when I took the key out of the ignition. Or locked the keys in the car almost as regularly (after the hide-a-key was safely deposited in the glove box from the last time I had to use it whereupon I blithely tossed it there, otherwise concentrating on how to save the world, or get laid, or both at once like in the movies).

Stationed USAF in Athens, Greece in the mid eighties I purchased a Fiat 127 hatchback. Brilliant little car. Simple, easy to work on. Holy crap.... the lights extinguish when the key is removed! The driver cannot lock his door from the outside WITHOUT USING HIS KEY!!!!!! This car was heaven sent for my type. I couldn't believe my luck. These two features saved me untold agonies over the course of two years driving it. I'm not saying this was especially clever of the Italians. Uhh, sensible? They must have looked to our vehicles and wondered at a few of these idiocies.

When I got back to the States, I purchased a little gold 1986 Honda Civic. FIRST order of business was rewiring the main fuse panel under the dash to energize the headlamp relay off of the ignition. Easy. Done. Next was to remove the driver side door panel, remove the circlip casing from the lock mechanism which retains the key tumbler pins, remove them, and toss them over the back fence into the weeds. The door still locked from inside and out, but could be opened with any key on earth. Only I knew that. No thief who tries the door handle and finds it locked is going to deduce this... he'll put a brick in the window first, like any other car. And if he's just trying to use my car to signal his comrade's subs he's just SOL.

Highly recommend all that. Sorry for the massive missive.
I like this guy ....what a great site...
 
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