1978 FJ40 - stock wiring. Tried wiring this every which way, and cannot get it to only buzz when the lights are 'on' and the ignition is 'off'. Suggestions?
Headlight minder buzzer (4 Viewers)
- Thread starter SteveH
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Yes. But I'm the last person to take elactrical advice from. Most of the LandCruiser electronics I do not understand at all. The rest is a complete mystery.
I bet that kit you bought is for an American vehicle.
A wise mechanic once shared his secret for Toyotas with me. "Think of how a US vehicle would be, and then do the exact opposite". Words to live by.
What I would do, and which you should not unless you are really desperate, is to mount that buzzer securely to the firewall where it's hard to reach, make a good ground with many freshly drilled holes and mount the ground wire securely with an oversized bolt. Attach the hot wire from the buzzer to a fancy light up toggle switch wich you place in an extra hole that probably already exists in your dash. Take the last wire from the toggle switch and tap it into the closest hot wire. Doesn't matter where it goes. Wrap that tap with mass quantities of black tape. No, more than that.
Then, whenever you pull into a parking spot, with headlights on, shut off the engine, flip the buzzer toggle to "buzz". Turn off your headlights, flip buzzer toggle to "not buzz" and exit the vehicle.
Then, always do what every other LandCruiser driver ever has done...glance back at it as you walk away to make sure the headlights are off.
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- #3
I'm so paranoid about getting hit by some moron that I now turn my lights on every time I drive the truck (day or night) and just old enough that I sometimes forget to look back at the truck as I'm walking away! That's the paradox of getting old.
Thanks - that's an interesting approach and would work. I was noodling this over and also concluded that I might be able to use a gauge light on the hot side, and another switched circuit that is cold at the right time, and fake the buzzer into working that way. The OEM fuse box is just too 'dumb' (lacks switched fuses) to make this work as instructed. I'm sure there's a way, and I'll post it here when known.
Thanks - that's an interesting approach and would work. I was noodling this over and also concluded that I might be able to use a gauge light on the hot side, and another switched circuit that is cold at the right time, and fake the buzzer into working that way. The OEM fuse box is just too 'dumb' (lacks switched fuses) to make this work as instructed. I'm sure there's a way, and I'll post it here when known.
There are switched fuses. Anything that requires the key on in the ignition switch is a switched fuse. The ignition switch doesn't have poles for all the switched circuits. What the ignition switch does is feed a section of the fuse block when turn on. Exception is the accessories circuit which is switched but that fuse is feed by it's own circuit.
I would suggest finding the wire going to the rear tail lights and hook the one for head lights there. Tail lights are on both with head lights and parking lights. Older 40 series parking lights were not on with the head lights.
Wouldn't mind giving this a try but appears.the 3M kit you have was NOS. This would be really easy to make with a couple of 12 volt relays and a 12 volt buzzer. Just need to hook the head light relay to the normally open point so it close with tail lights on then wire in series to a normally close points on one from fuse that only has power with ignition on. Then to the buzzer. Tail lights on and ignition off you have a complete circuit to the buzzer. Light the Toyota headlight upgrade to Halogen lamps pre made kit make it easy. Not sure want to go thru the hassle of building the harness with relays and buzzer. I have 80 rear E locker I might consider making a special harness so it operates just like the factory unit. Not sure the aftermarket units are designed to the light flash when the locker doesn't engage when it should or doesn't disengage when switched off. Requires a few more relays but easy enough to do.
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- #7
Ultimately. I believe this buzzer works in principle by having the hot wire attached to the headlights, and the cold wire going to a source that is 12v ignition switched, and otherwise grounded. So, when the lights are on, and ignition off, the buzzer sees 12v and sounds. The rest of the time, the buzzer sees 12v on both wires and is quiet since there is no voltage differential.
If I daydream enough during office meetings. I should be able to come up with a wiring scenario that will make it work. @Living in the Past method would surely work, too.
If I daydream enough during office meetings. I should be able to come up with a wiring scenario that will make it work. @Living in the Past method would surely work, too.
SteveH is right. It's done like the alternator/generator idiot lights on a GM car. Hook the hot wire for the buzzer to a constant 12v source. When the ignition is ON, the "ground" wire for the idiot light (or buzzer in this case) is fed 12v from the ignition switch so the light (or buzzer) doesn't see anything but a balanced 12v on both of its wires, so the light is off, or the buzzer is quiet. When ignition gets switched to the "off" position, the idiot light no longer receives the balanced 12v on the "ground" wire, and the light comes on, (or the buzzer in this case) sounds. The "ground" when the ignition switch is off will come from all the devices that are connected to the switched lug of the ignition switch.
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Then it would buzz when the other wire is on any of the hot fuses, either side of any good fuse. With the engine off and headlights on voltage will read the same everywhere on the hot the fuses in the fuse block. Even the buzzer positive wire (which does show) would show any voltage drop. The ignition side will have ground with resistance. That will vari vehicle to vehicle. I do agree the ignition is used as the ground, my bad as it doesn't show one like doesn't show a positive wire for the buzzer. But can't see it not buzzing headlights on or off. Wired after the headlight switch will work because neither wires are hot and show ground. The buzzer would need a diode otherwise with headlight off and ignition on it would buzz.
0v does not equal ground
Curious of resolution to this. Only says you need to hook two wires to fuses. Plastic case just adheres somewhere. That means no dedicated ground. Have to assume the path ground is on the ignition side in series. Light load from a buzzer design for to only be used for a short time can see working. It's the other wire on the hot side of the fuse block I don't understand. The switched side of the headlight switch I can see working.
It looks like it is getting power from the light circuit and grounding through a load on another fuse when the ignition is off.
I agree just not sure how it's suppose to know when the lights are on taping into the hot headlight fuse on the fuse block. Voltage is the same on all hot fuses.
Looks like a good write-up on how one version works here: Above my head though.
makingcircuits.com
Headlight Reminder Warning Circuit
The car headlight reminder circuit can be used to warn the driver that he has left the car's headlight switched on after leaving the car. You then are up
makingcircuits.com
Looks like a good write-up on how one version works here: Above my head though.
Headlight Reminder Warning Circuit
The car headlight reminder circuit can be used to warn the driver that he has left the car's headlight switched on after leaving the car. You then are up
Both these show at least four connections. The 3M unit uses only two. Your second is confusing without showing how that relay work. Both show dedicated grounds. Plus using headlight parking light/parking light circuits or as I suggested the tail light circuit. That because my early FJ40 the parking lights are not on with the headlights. More likely no to notice parking lights than headlights..particularly around dusk or dawn. Stock cluster lights are easy to miss if it isn't completely dark. My biggest fear is going on an early morning hunt and leaving the vehicle at dawn and not notice the parking lights are on. Come back hours lately to a dead battery.
I'm, not an EE. So don't really understand any of this. But this is the datasheet for the relay. https://www.citrelay.com/Catalog Pages/RelayCatalog/J107F.pdf
My guess is the Relay is Normally Closed. So if power is on at the headlights it passes thru to the buzzer. When fed 12 Ign the relay break connection and disables the buzzer.
edit: Had my verbage wrong.
I've totally have killed a few batteries doing this. So would love to figure this out. Bonus if it works with both the fogs and headlights.
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@ToyotaMatt informed me the 40 series fog light are wired like the later models. The power to the fog light switch is fed for the low beam headlight circuit. If thru a pilot relay oe directly off the low beam highlights it would still buzz. Would have to put a thought into it but guessing a second relay feeding the buzzer would work as well to any aftermarket accessories you want to be sure were off. Like my two 4Runners and Sequoia how will turn off the headlight after a certain amount of time or even a door left open will stuck off after a few minutes. It turning on a dome light or headlight lights for that matter that will kill a battery. Found that out the hard way on my Sequoia. Unloading thru the second door and turning on the light behind the third row seats manually killed the battery after a few days of not using the vehicle. Because the far back light was turned on manually it stayed on. Because the back hatch won't open in the garage unloading thru side doors is fairly common.
