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    #16
    Originally posted by gadget73 View Post
    well, Vols = current * resistance, or current = volts / resistance, so with 12 volts across 0.6 ohms, you're at 20 amps. Add in wire resistance and its probably still around 10 amps. At 25 ohms, you're right around half an amp of current. Higher resistance = lower current, directly in proportion.
    Thanks for these equations, gadget! I'll keep them handy.

    Originally posted by sly View Post
    anything under 1 ohm should be considered bad. 13.6V is about the nominal for most any current calculation... so 0.5 ohms should give you over 26 amps. You want horns that are higher than 1 and much higher preferably. I didn't check the new Wolo horns I got at the parts store for my 88, but I can when I get home. 25 ohms sounds like a very good one to me. I'm betting the one from Ashley's car is also close to being done too.
    Originally posted by sly View Post
    the horn fuse should be 20A but it's also got a few other things on that circuit. If one horn is less than 1 ohm, that means it's pulling more than 12 amps when you poke the button. Not a good scenario for fuse longevity. A good horn should pull less than or maybe 1 amp How else can HiFiMerc have 11 horns on his car and still only be using the one circuit. If the good ones are about 25 ohm... then they will be pulling about half an amp. I'm thinking you're dealing with old car syndrome with both cars a bit here. Kinda like I did with my 88, but you don't have a short between the fusebox and firewall that just pops the fuses as fast as you can poke them into the fusebox. At least you have to push the horn button to actually blow the fuse. Though it might be a good idea to check for wire issues. The horn wires are pretty exposed. At least on every car I've seen, the last 6-10 inches are not in loom at all.
    Well I did some more futzing with the horn from my car and the ones I pulled from the yard. I kept turning that attenuation screw clockwise since the manual said clockwise would reduce the amperage through the horn (and thus increase resistance based on my thoughts and now that equation). Initially I had my multimeter set up to read the current flow through the thing (I had it wired right based on several diagrams I saw, internet makes everyone an expert right? ) but it would not read at all and horn would not blow. So I set it up to read resistance and kept turning right to the point the circuit went "open." lo & behold right before that happens there's about a 1/4 of a turn where I can see the resistance jump from about 0.5 ohms to a steady 1.4 - 2.1 ohms. Trouble is once I blow the horn the resistance drops back down to about 0.6 ohms. Manual says to pinch the housing where the screw is to secure it in place yet I'm not convinced by that, it wasn't pinched in the first place. Oh, all horns I have will blow no matter this resistance number so all the ebay listings I'm seeing aren't promising unless they have a ohm number.

    Yes, luckily in my case the thing will only blow a fuse if both horns are connected. If I simply unplug both of them I can press the button and hear Mr. Relay click and stay clicked until Ashley gets tired from holding the horn button. Plug either horn in, one at a time and that horn will work without fuse failure. Both and it's bad news bears for fuse.

    11 horns? Whoa. Yeah the exposed wiring was a shocker for me but figured that was a Ford special as the JY car, my car and her car were all like that. Cleaned them up, threw dielectric grease on there and adhesive lined heat shrink to make me feel good. What's a Wolo horn? What does it sound like?

    I made a typo for Ashley's low note horn, that thing measured 1.4 or 1.6 ohms, but probably still close to death. She reported yesterday that her system is fine with junkyard horn, her horn blew for 5 seconds or so until she got tired from hearing it.

    Originally posted by 85crownHPP View Post
    If it acts the same with horns that are nice and loud on the other car, I'd suspect a pinched wire or other short somewhere. There's a good chance the horn wires are in the same harness as the alternator wiring that goes into the interior, how deep did you go when you wired up the 3G?
    Current has to be flowing somewhere excessively for a fuse to blow, try to think of any wiring you could have disturbed between the relay and the horn, even in past projects.
    I'd rig up some jumper wires and test all the horns directly with a battery, just to triple check them.
    I think I went the lazy man's route with the 3G install, I only ran a fatter charge wire, connected charge sense (yellow) wire to stud on the starter solenoid and then connected the white stator wire to the "D" shaped plug, I did not go into the interior..

    I asked her about her horns yesterday and she couldn't remember if they worked without a hitch. I tried them this morning and could not get the fuse to blow. So either they both work or one died on me, probably the low note one.


    Oh, on a side note it looks like horns from older cars are direct fits for pre 1990 box stuff. Looks like Mark V horns fit and also some early mopars also have the same design with lo/hi designation, all made by Spartan.
    1985 LTD Crown Victoria - SOLD
    1988 Town Car Signature - Current Party Barge

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      #17
      Alright, I've had it. I ripped off my high note horn and it's a whopping 0.8 ohms at best. So is the other I once though was above 15 ohms. With that said, none of the horns tested in yards have ever over 1 ohm.

      I'm going to buy a breaker that fits in that fuse slot as I've blown through at least 15 fuses with trial and error scenarios, so should save me money in the long run.

      My solution is this: Horns work n sound just fine. I want to just place a resistor in series so current never exceeds 20 amps with both horns blowing. 1 ohm means around 144 watts at 12 volts, right? Something around 13 amps too I think. I don't know where I can get resistors that will work with what I'm trying to do and not fail. What about this?
      http://www.ebay.com/itm/1-5-Ohm-1-5R...25.m3641.l6368
      One of each just before each horn is what I'm thinking. Plus I don't want to run skuzzy rusty junkyard horns on my rust free car, if anyone has a nice set of horns that measure over 1.5 ohms then I'd be more than happy to shoot you an offer.
      1985 LTD Crown Victoria - SOLD
      1988 Town Car Signature - Current Party Barge

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        #18
        Kinda why I just got the WOLOs at O'Reilly.

        Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
        rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
        Originally posted by gadget73
        ... and it should all work like magic and unicorns and stuff.
        Originally posted by dmccaig
        Overhead, some poor bastards are flying in airplanes.

        Comment


          #19
          I looked them up just now and saw some single terminal horns that would fit with some modification. If I have to go that route I guess I will, I like the sound of my OEM horns though. The resistor thing seems like a good idea. You and gadget are more electrically savvy than I so I'd like to know if what I listed will work or if there are cheaper, smaller & more local alternatives to that resistor.
          1985 LTD Crown Victoria - SOLD
          1988 Town Car Signature - Current Party Barge

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            #20
            Alright, so no one has any input on the resistor deal? Anyone know of a place I can get resistors other than ebay? What about those inside instrument clusters and stuff? Any cars I can rip them out of???
            1985 LTD Crown Victoria - SOLD
            1988 Town Car Signature - Current Party Barge

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              #21
              Any resistor will just quiet or disable the horns. If you put in a 1ohm resistor and the horn is at 0.8, the horn will get less than 6 volts and probably won't sound off at all. The Wolos I used are louder than the stock horns by a good bit too.

              380-2T and 385-2T

              I'd just bite the bullet and replace them unless you're trying to go for full original with your car. In that case, good luck finding some good horns. OE should be about 1.5 ohm for an okay one. No clue what a good one rings out to though.

              http://www.oreillyauto.com/site/c/de...802T/01029.oap
              and
              http://www.oreillyauto.com/site/c/de...852T/01029.oap

              Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
              rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
              Originally posted by gadget73
              ... and it should all work like magic and unicorns and stuff.
              Originally posted by dmccaig
              Overhead, some poor bastards are flying in airplanes.

              Comment


                #22
                Indeed. Fix the horns, don't rig the electrical system to cooperate.
                86 Lincoln Town Car (Galactica).
                5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                91 Lincoln Mark VII LSC grandpa spec white and cranberry

                1984 Lincoln Continental TurboDiesel - rolls coal

                Originally posted by phayzer5
                I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                Comment


                  #23
                  I would like to keep the thing as original as possible. If those horns came attached to the same "L" bracket the OE ones are on I'd buy them right now, but it looks like I'll need to take the spares I have, cut the horns off and then punch out the center to accommodate the WOLO units. Does that sound right or is there an easier way to get the factory horns off the brackets? This will probably happen as I can sand blast, pretreat & powdercoat the brackets at work. So those horns sound the same as factory but louder, right?

                  One last bit of babble...

                  I did some calculations and if I assume each of the current horns are at 0.8 ohms, system resistance = 2.5ohms, which means system current works out to be 5.76 amps, assuming 14.4 volts. Yet with what's going on it doesn't make sense as one horn alone (lo or hi note) = 18 amps and I can run either horn indefinitely yet when I combine the two the fuse blows in an instant. There's gotta be something I'm not accounting for here, what is it? The set-up for the horns is a parallel circuit, right?
                  1985 LTD Crown Victoria - SOLD
                  1988 Town Car Signature - Current Party Barge

                  Comment


                    #24
                    Pretty much you're right about the brackets. The tone is a dink higher on the high tone than the previous horns, but that could have been my old worn out high tone being flat.

                    As for the resistance... the horns are not in series, so their resistance is not additive. They are in parallel, so their current is additive. They are basically wired up with each one set to be between battery and ground individually.

                    Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
                    rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
                    Originally posted by gadget73
                    ... and it should all work like magic and unicorns and stuff.
                    Originally posted by dmccaig
                    Overhead, some poor bastards are flying in airplanes.

                    Comment


                      #25
                      Thanks sly, I'll get to that when I can, until that's all wrapped up I'll just unplug one of the horns.

                      I think you read the last response wrong; I used some electrical tool box site to figure out resistances with parallel circuits and from the equation we simply take the reciprocal of each resistor (the horns) and then add them together; 2(1/0.8)=2.5ohms, which is only 5.5ish amps at best, so the horns shouldn't blow the fuse when run together yet they do. If I unplug one of the horns now I just have a series circuit -> 14.4v/0.8ohms= 18 amps. With one horn unplugged (Doesn't matter which one) the horn will work without blowing a fuse. I can then unplug the one that was working and plug in the one that was unplugged and same thing. What baffles me is that given the equations and what not, why the hell is this thing blowing fuses with both horns hooked up? Seems like it would have more potential to blow a fuse with just one...
                      1985 LTD Crown Victoria - SOLD
                      1988 Town Car Signature - Current Party Barge

                      Comment


                        #26
                        parallel resistance is 1/R1 + 1/R2 = 1/Rt. In the case of identical values, you simply cut it in half, ie a pair of 0.8 ohm horns in parallel is 0.4 ohms. 14.4 volts across 0.4 ohms is 36 amps.

                        If you have uneven values, or more than 2 things, then you actually need to do the math.

                        Whenever you parallel things, the total resistance will always be less than the value of the smallest resistor.
                        Last edited by gadget73; 11-18-2015, 06:25 PM.
                        86 Lincoln Town Car (Galactica).
                        5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                        91 Lincoln Mark VII LSC grandpa spec white and cranberry

                        1984 Lincoln Continental TurboDiesel - rolls coal

                        Originally posted by phayzer5
                        I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                        Comment


                          #27
                          we're all actually saying the same thing in different ways. current being additive means the current from one horn with full voltage added to the current of the other with full voltage. Works out to the same thing.

                          Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
                          rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
                          Originally posted by gadget73
                          ... and it should all work like magic and unicorns and stuff.
                          Originally posted by dmccaig
                          Overhead, some poor bastards are flying in airplanes.

                          Comment


                            #28
                            Oh, so that's what was missing from the equation I was looking at!

                            Site gave an example like you mentioned gadget but I forgot the last part of it which said to take the reciprocal of the total, too. 36 amps, that explains the almost instantaneous fuse failure. Thanks for helping me out fellas.
                            1985 LTD Crown Victoria - SOLD
                            1988 Town Car Signature - Current Party Barge

                            Comment


                              #29
                              That Ohm guy and his damn laws.

                              Parallel current adds. Parallel resistance subtracts, and one happens because of the other.
                              86 Lincoln Town Car (Galactica).
                              5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                              91 Lincoln Mark VII LSC grandpa spec white and cranberry

                              1984 Lincoln Continental TurboDiesel - rolls coal

                              Originally posted by phayzer5
                              I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                              Comment


                                #30
                                Doh moment for sure.

                                How was Arlo?
                                1985 LTD Crown Victoria - SOLD
                                1988 Town Car Signature - Current Party Barge

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