Headlight Warning Buzzer circuit for older cars

[Lachlan]

Hey guys,

I've recently developed an electronic circuit that sounds a warning buzzer if you leave the lights on while the ignition is off. I've tested it, and it works exactly as I want it to. I'm yet to build any, but there are companies who will print circuit boards if you have a large enough number of orders.

It's a pretty straightforward circuit; takes a battery input, ignition input from the accessory post, a signal input from a headlight relay and outputs an annoying buzzing sound (remember, this is a good thing). The only things you'd need is a 12V electrical system, and preferably (but not required) headlight relays. Knowing that this issue is endemic to old cars, not just old jeeps, is anyone interested in getting one of these made? I could either get them made in bulk for you, or post the circuit diagram on AJOR - whichever is easier.

[carvesdodo]

Originally Posted by Lachlan

Knowing that this issue is endemic to old cars, not just old jeeps, is anyone interested in getting one of these made? I could either get them made in bulk for you, or post the circuit diagram on AJOR - whichever is easier.

heh heh ... the wheel is reinvented ....................... again

Sounds like you want to deal with a 70's issue ... the same as we did in the 70's.

Headlight Reminder, kits and complete units have long been available ...... but congrats on using your noggin and coming up with a fix for yourself.

May be room on the market for a more "interesting" unit .... with some extra features if you could turn your hand to that ?

[Lachlan]

heh heh ... the wheel is reinvented ....................... again

Lol, I guess I should've expected that!

I never did look hard enough for a ready-made kit, but I definitely wanted to deal with (eliminate) the issue, and a buzzer seemed like a convenient answer. Now that I've had a crack at wiring stuff together, I'm gonna keep working on it to see if I can work some useful stuff into the circuit. So if you (or anyone reading) have any suggestions as to what might be useful, feel free to put it here where everyone can see it.

[MR EXTREME JEEP]

Thats funny. The first thing JK'ers do is eliminate the door charm. And here you are installing one.
Maybe add a little "dingggg!" bell for when the coffee is ready I mean for when the door is open.
Only kidding mate. Well done. If you can get the designed refined to a two wire plug in and the overall size of the unit is small it should be a seller.
Always thought Carves was a 60's guru. But the 70's seem to be more his thing.
Good luck M8.

[carvesdodo]

Originally Posted by Lachlan

So if you (or anyone reading) have any suggestions as to what might be useful, feel free to put it here where everyone can see it.

Not a lot of new stuff in the vehicle industry anymore ..... just different ways of doing things thats already been done ...

Gotta laugh at stuff like the big dollar advertising on headlights that move with the steering ... when its just a fancy copy of something citroen did yonks ago

Maybe a bypass button/switch for those occaisions you want the lights on with the engine off/doors open ??

LED display for which door the kids didnt close properly ?? ... lets you abuse the right one .... instead of having all the doors opened & slammed shut in terror ....

Originally Posted by MR EXTREME JEEP

Always thought Carves was a 60's guru. But the 70's seem to be more his thing.

60s you just drove them for what they were,
70s you played with them,
80s you shook your head at the garbage being built,
90s you realised how good the 80s stuff actually was by comparison,
Post millenium you buy something reasonably decent from the 90s and hope it lasts until they take the drivers license away .....

[Gildo]

If you can incorporate several functions in one unit you may be on a winner.
With the 2 different inputs you have, you could display battery charge level- from the constant 12V supply, current usage- from the ignition supply.
Cant think of anything else right now but there's gotta be millions of things you could combine.

[Lachlan]

Too right about not being new stuff in the industry - the combustion engine has remained fundamentally unchanged for over 100 years, which is proof in itself. A bypass switch is something I want to wire in somewhere, but I'm not sure how. I was thinking of setting up a time delay circuit, so that the warning circuit only turned on once the ignition was on, then stayed on for like 30 seconds when you turn the ignition off. All this complicated electrical wizardry seems like a slap in the face to the simplicity of a '62 CJ6! :P

I think what I'll do is cover basic warning stuff, like handbrakes and headlights. A lot of the stuff like door indicators and whatnot can be wired using 12V switches and relays, rather than logic circuits. What I like about using logic gates, and what might be different to what's currently on offer, is that I can make different buzzing sounds for each problem. So intead of the TJ's bloody one-buzz-fits-all, the circuit could tell you exactly what you've left on (although you usually notice if the handbrake is on).

The charge level indicator would be cool, it'd combine a voltmeter and ammeter into one, more useful output. Possibly I could use a 12V supply from the alternator, rather than the ignition. That'd be able to tell you the alternator's current output, right? The circuit would only run when the engine runs, which would also solve the bypass switch issue.