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Sparkers… Flasher circuit.

| Posted in General Discussion on December 10, 2000 11:27am

*
I know this is not household electrical service, but I am hoping that someone here will have the answer. Until I figure out the answer to this question, I will be stranded out here in the boonies.

My truck kakked. Burnt up the transmission. I’ve been working on a car, trying to get it on the road, so I can have transportation. It was a ‘junked’ car. (Abandoned on the property of a friend of my dad.) When I was given the car, it had no headlights, tailights, etc. It had no horn. The ignition switch was totaly missing. (The whole, huge metal assembly, not just some small electrical part.) No turn signals. Bad alternator. Some of the wiring harness was fused from an electrical fire. Blower motor completely missing. Half the relays totaly missing. This is not by any means a total list of the things wrong/missing.

Long story short, I found a ‘donor’ car. 1 year newer. I now have most of the relays. Replaced the alternator. Sorted out/fixed the fused wiring harness. Got the headlights/drivinglights working correctly. Replaced the blower motor. Figured out which wires were for the brake lights, and isolated them, then built a complete new, (seperate), circuit for the brakelights, starting from the working switch at the brake pedal.

I have everything working now except the horn and the turn signals. Doing the horn will be child’s play, using an aftermarket headlight relay. However, I cannot figure out how to make the turn signals flash, if I were to make my own seperate circuit.

I made a small circuit with a light and a flasher unit in series, as the drawing below. The light lights well when connected directly to the battery. When the flasher is added in series like the pic, the light still lights, but is very dim. It did not flash. I left it connected plenty long enough for the flasher unit to get heated up, but it never started flashing. How do I make a very simple circuit that will flash ? If I can figure out the flash, I can build the rest of the circuit myself.

Thanks in advance.

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Replies

  1. Phill_Giles | Dec 09, 2000 09:00am | #1

    *
    Stupid questions first:

    1) did you reverse the polarity on the flasher to see if that worked ?

    2) did you check to see if the particular flasher you've bought requires it's own ground (ie: the flasher is on its own circuit and selects a relay for the lights) ? Sometimes this is not obvious (like achieving ground through a chassis (mounting) screw.

    1. Luka_ | Dec 09, 2000 09:04am | #2

      *Luckily I actualy thought of these things and don't have to feel stupid saying that I hadn't LOLYes, I tried reversing the polarity on the flasher. I also grounded out the body of the flasher unit itself in case that mattered. I also tried this with three different flasher units. Not very likely that I had 3 flasher units that were bad.

      1. Phill_Giles | Dec 09, 2000 09:51am | #3

        *But wait, there's one more stupid question - did you try this with two bulbs ? Not just any two bulbs, but two actual turn sinal bulbs, in series (or is it parallel, I can remember this late at night) ? You have to draw enough current to drive the flasher and a single bulb may not be enough load.

        1. Luka_ | Dec 09, 2000 10:10am | #4

          *No. I didn't. I will do so tomorrow. I will do it with the bulbs parallel instead of in series, since, in essence, that is the way the circuit would run in the car. The common power runs from the switch out to both the front and the back of the car, through two bulbs, and then back to a common ground, (the car body). Making the bulbs a parallel circuit.Looking at the wiring diagrams in all the different car books I have, it looks like the most common flasher circuit runs like this... Positive from the battery to one pole of the flasher unit. From the other pole of the flasher unit to the switch on the steering column, where it is routed to the right or left circuit. From there it goes straight to the bulbs, then to ground. According to this, my simple circuit should have worked. But it didn't.The fact that the single bulb that I used, glowed at less than half the brightness after the addition of the flasher has me in a quandary. It's obviously doing something. So, putting two bulbs on the circuit will draw more electricity through the flasher unit ? I have been under the impression that a bulb, (load), equals resistance. It seems to me that putting more resisitance between the flasher unit and either pole of the battery would cut the amount of power getting through the flasher unit. Maybe the load is too much on the flasher unless there are two bulbs ?I have a feeling that I am forgetting something elemntary here. (Like the fact that running two bulbs in parallel is not increasing the resisitance, but running them in series would...) I figure it's something really stupid that I am missing. LOL

          1. Woodcarver_Ron_Wiener | Dec 09, 2000 03:13pm | #5

            *Two bulbs of equal wattage in parallel will reduce the resistance by 50%. Think of it as a waterline. Reducing the diameter of the water line is a form of resistance. Branching a water line into two parallel lines effectively expands the diameter, removing some resistance.Voltage is comparable to water pressure.Gallons per minute (flow rate)is comparable to amperage.Gallons per minute times water pressure is comparable to wattage.

          2. Ryan_C | Dec 09, 2000 04:09pm | #6

            *Phil might be onto something. When a bulb goes in my car, the flashing slows down to a snails pace. If two bulbs go (I've got four on each side and that's not much incentive to change them if only one's bad)the flashing stops and the lights just stay on.

          3. G.LaLonde | Dec 09, 2000 04:18pm | #7

            *Luka, I have done this many times with construction equipment that we drive on the roads, so I know it's easy to do. We usually are hooking up two flashing lights high on the cab ( 12volt ) We get our flashers at the auto parts store. They are not the kind you have. (typical automotive plug in style)... They are little metal boxes about 1"x 1/2" that come in different current ratings. I think you just have a flasher that is too much for the voltage or load you have. These units must be grounded.

          4. Frank_DuVal | Dec 09, 2000 08:49pm | #8

            *Just a few quick tips, need to go out of town now...There are two types of flasher units with two terminal like yours. The OEM type and the replacement 522 series. Sounds like you have the 522 series, which needs a big enough load to heat up the bimetal strip and short out the heater to light the bulbs. The lights do not come on until the heater heats up!Is the filament of the turn signals in rear the same filament as the brake lights? If so, this approach you have will not work at all.Why reinvent the wheel? You have a donor car, just transfer the turnsignal switch, brake lights, harness to project car.GLaLonde refers to a three wire flasher that is made to flash with out reguard to load. Great for trucks, trailers, industrial equipment, but the flashers usually cost $20.Frank DuVal

          5. Rich_Beckman | Dec 10, 2000 10:36pm | #9

            *Luka,If your picture is accurate, I would suggest substituting wire for the pipe cleaners.Also, if this was an abandoned car, how do you go about getting a title so you can get a liscence plate?Rich Beckman

          6. Luka_ | Dec 10, 2000 11:22pm | #10

            *LOLThe problem is solved. I found a variable load thermal flasher that will flash no matter how many or how few bulbs are on the circuit. (Only cost a dollar more than the 'normal' ones.) Made up the same test circuit and it worked. Then it also worked with two more bulbs added, so I can now make my own circuits for the turn signals. (Now the car is just waiting for me to get the gumption to go out there and crawl around in the freezing mud and make a couple circuits.)As for the liscence... The car sat on the property where pops is, for 4 years. He called the county sherriff out to do a junk vehicle report on it. Then the landowner gave the car to me. Pops trailered it over to my house, and I fixed it. With it running I had to take the car to the state patrol office for a special inspection. Had to take the original junk vehicle report with me, as well as a note from the landowner saying that he had given the car to me. Near as I could tell the state troopers just crawled around and looked at numbers all over the car. They didn't even care that it had no horn or turn signals. They said that the sherriff's deputy had made the wrong report, it should have been an abandoned vehicle report instead of a junk vehicle report. (Apparently with an abandoned vehicle, you can get plates and/or tabs for it right away, but you have to wait 3 years to get a clear title.) I told them this was my only means of transportation, (They were going to make me go back home and wait a month for another sherriff's deputy to come out and make another report, then up to 3 more months after that to get an appointment with them for a re-inspection.), and they took all my paperwork into the office, made me sit in the car, to the side, for about a half hour, then came back out with the completed paperwork I needed to take to the license plate place. I now have brand new plates for the car. A clear title is supposed to arrive sometime in the next two weeks. Now, I am legal on the road. (As soon as I can afford the insurance. LOL)I am constantly amazed at the blessings I recieve. I certainly don't deserve them. BTW : It was thanks to help from one of our own here, that I was able to afford this. You know who you are, I thank you from the bottom of my heart. This situation could have become a dangerous one for me, or at the very least one that was too depressing for me to continue. Now I will be able to get to town in an emergency, etc. Thank you.

  2. Luka_ | Dec 10, 2000 11:27pm | #11

    *
    I know this is not household electrical service, but I am hoping that someone here will have the answer. Until I figure out the answer to this question, I will be stranded out here in the boonies.

    My truck kakked. Burnt up the transmission. I've been working on a car, trying to get it on the road, so I can have transportation. It was a 'junked' car. (Abandoned on the property of a friend of my dad.) When I was given the car, it had no headlights, tailights, etc. It had no horn. The ignition switch was totaly missing. (The whole, huge metal assembly, not just some small electrical part.) No turn signals. Bad alternator. Some of the wiring harness was fused from an electrical fire. Blower motor completely missing. Half the relays totaly missing. This is not by any means a total list of the things wrong/missing.

    Long story short, I found a 'donor' car. 1 year newer. I now have most of the relays. Replaced the alternator. Sorted out/fixed the fused wiring harness. Got the headlights/drivinglights working correctly. Replaced the blower motor. Figured out which wires were for the brake lights, and isolated them, then built a complete new, (seperate), circuit for the brakelights, starting from the working switch at the brake pedal.

    I have everything working now except the horn and the turn signals. Doing the horn will be child's play, using an aftermarket headlight relay. However, I cannot figure out how to make the turn signals flash, if I were to make my own seperate circuit.

    I made a small circuit with a light and a flasher unit in series, as the drawing below. The light lights well when connected directly to the battery. When the flasher is added in series like the pic, the light still lights, but is very dim. It did not flash. I left it connected plenty long enough for the flasher unit to get heated up, but it never started flashing. How do I make a very simple circuit that will flash ? If I can figure out the flash, I can build the rest of the circuit myself.

    Thanks in advance.

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