i found this after searching a hella lot. i find it on www.instructables.com/this site of all sites. i should have looked there first. d'oh

this is for anyone using electronic flashers in their cars. does not work with thermal type.
this looks to be just for the 3 prong kind. im going to get a 2 prong and see what i can do with it.

quote intro Automotive electronic flasher rate modification. For anyone who has added LED bulbs to their vehicles turn signals or brake lights. Since the LED bulbs use less Amps than normal bulbs, the flasher unit thinks there is a bulb burnt out and doubles the flash rate. This instructable will show you how to alter the flasher module in your car for variable flash speeds. Note: This is for electronic relay type flashers only. This will not work on thermal flashers. step 1 The flasher. Here is the flasher I modified. Since I am using the flasher in my car, I just pulled this one out of another '97 Cougar at the junkyard. There are two tabs holding the circuit board in, just pry them loose with a small screwdriver. step 2 Inside the Flasher The inside of the flasher is pretty simple. it consists of an open frame relay, a couple resistors, a capacitor, a shunt, and the controller IC. I looked up the part number to find the schematic. For this particular flasher, the 100k Ohm resistor connected to pins 4 and 5 will be removed and replaced with a 500k Ohm variable resistor. step 3 Remove the resistor Simply desolder the resistor fromt he board. Careful not to overheat and burn out the IC. step 4 Variable resistor. Here, the new variable resistor is connected. There are three pins on the variable resistor. The two on the ends connect to the 500k Ohm resistance. The center pin connects to the wiper. Connect two wires, one to the wiper and another to one of the side pins. Once you set your flash rate, you can measure the resistance on the variable resistor and replace it with a fixed resistor if you want. I left it variable because I plan to continue to add LED bulbs to my vehicle. step 5 Connections. If you wish to test the unit outside your vehicle, connect everything as follows: B = Battery + E = Ground L = Lights (This is a positive output. Connect the other lamp wire to ground.) *These connections may vary for different vehicles!* step 6 Schematics Here is the original schematic for my flasher unit and the altered version with the variable resistor. I have added the part values that are in my unit to this schematic.

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First LX9 Fiero GT, 1987 | My Fiero Fuel Economy | MPG Display for OBD I
Youtube Videos of My GT | 87 GT Inside Test Run | 3500 Fiero GT Test Run 01
3500 Fiero GT Test Run 02 | 3500 Fiero GT Test Run 03 | 3500 Fiero GT Test Run 04
If you can't fix it with a hammer, you've got an electrical problem
Fiero's are people too. We pay just as much attention to them, if not more than our loved ones
screw paying those bastards. im not going to become rich by paying for things.....

[This message has been edited by americasfuture2k (edited 07-25-2009).]

To help with your modified schematic remove the Right hand outer leg of your Variable. With it connected you turn the 500K into a 250K. Without the right hand connected is how you have yours wired. just remove that leg and your schematic will be perfect.

rock on, once again stu, thanks for the electronics knowledge help! i dont think i can give you any more +'s

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First LX9 Fiero GT, 1987 | My Fiero Fuel Economy | MPG Display for OBD I
Youtube Videos of My GT | 87 GT Inside Test Run | 3500 Fiero GT Test Run 01
3500 Fiero GT Test Run 02 | 3500 Fiero GT Test Run 03 | 3500 Fiero GT Test Run 04
If you can't fix it with a hammer, you've got an electrical problem
Fiero's are people too. We pay just as much attention to them, if not more than our loved ones
screw paying those bastards. im not going to become rich by paying for things.....

quote Originally posted by DIY_Stu: ... remove the Right hand outer leg of your Variable. With it connected you turn the 500K into a 250K.

Better check that again. Either way, the resistance with the wiper at one end of its travel will be 500k. With the wiper at the other end if its travel the resistance will be zero. With the wiper in the middle the resistance will be 250k (assuming a linear taper).

Where did you purchase your variable resister?

You know you are right. It doesn't matter.

With it connected if the wiper fails it results in a 500K flash pattern. Without it connected it'll just fail.

Good catch. Thanks.

quote Originally posted by DIY_Stu: You know you are right. It doesn't matter.

I've done the same thing to myself more than once.

I did somewhat the same thing here on PFF in the discussion concerning headlight wiring changes that would keep the low beams on even when the high beams were selected. I proposed several electronic solutions, and even posted appropriate part numbers, until I recognized that a single well-placed wire jumper would accomplish the same thing. See this thread.

Back in the 1960s I designed an all-electronic voltage regulator for motorcycles. I even developed a fairly complex circuit to prevent reverse current whenever the generator output voltage was lower than the battery voltage. After several weeks of design iterations, I forced myself to think of the problem in terms of current rather than voltage; only then did I finally realize that a single silicon rectifier diode would accomplish the same thing, but with a lot less cost and complexity!

quote Originally posted by IXSLR8: Where did you purchase your variable resister?

They are very common parts. I realize that they're not electronic toys or cell phones, but Radio Shack may still carry of few of them anyway; I would check there first. After the folks at Radio Shack give you the blank stare, there should still be one or two local electronic supply houses in the Portland area you can try, if you can find them. On-line, DigiKey and Mouser Electronics are good sources if you know what you're looking for.

[This message has been edited by Marvin McInnis (edited 06-14-2009).]

one thing tho, thats for a 3 prong flasher. we use the 2 prong. how can we make this work?

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First LX9 Fiero GT, 1987 | My Fiero Fuel Economy | MPG Display for OBD I
Youtube Videos of My GT | 87 GT Inside Test Run | 3500 Fiero GT Test Run 01
3500 Fiero GT Test Run 02 | 3500 Fiero GT Test Run 03 | 3500 Fiero GT Test Run 04
If you can't fix it with a hammer, you've got an electrical problem
Fiero's are people too. We pay just as much attention to them, if not more than our loved ones
screw paying those bastards. im not going to become rich by paying for things.....

That is a very common way of doing audio volume controls. By leaving the one lead hanging it left a source for noise pickup so they always tied it to the wiper.
Probably would not matter in this application.

yea, i dont think interference of that little would matter on this

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First LX9 Fiero GT, 1987 | My Fiero Fuel Economy | MPG Display for OBD I
Youtube Videos of My GT | 87 GT Inside Test Run | 3500 Fiero GT Test Run 01
3500 Fiero GT Test Run 02 | 3500 Fiero GT Test Run 03 | 3500 Fiero GT Test Run 04
If you can't fix it with a hammer, you've got an electrical problem
Fiero's are people too. We pay just as much attention to them, if not more than our loved ones
screw paying those bastards. im not going to become rich by paying for things.....

quote Originally posted by americasfuture2k: one thing tho, thats for a 3 prong flasher. we use the 2 prong. how can we make this work?

quote Originally posted by americasfuture2k: one thing tho, thats for a 3 prong flasher. we use the 2 prong. how can we make this work?

I know they make a 2 prong electronic flasher though. I have this one. http://info.rockauto.com/SM...tail3.html?EFL1.html or
http://info.rockauto.com/Tr...Detail.html?EL12.jpg
Believe you would change the time on it by changing the capacitor.

[This message has been edited by Dodgerunner (edited 06-18-2009).]

yea ive looked at those. just pictures and at the package. i dont think these use an IC like what the main subject covers. im feeling a search in order.... gotta waste some time at work ya know?

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First LX9 Fiero GT, 1987 | My Fiero Fuel Economy | MPG Display for OBD I
Youtube Videos of My GT | 87 GT Inside Test Run | 3500 Fiero GT Test Run 01
3500 Fiero GT Test Run 02 | 3500 Fiero GT Test Run 03 | 3500 Fiero GT Test Run 04
If you can't fix it with a hammer, you've got an electrical problem
Fiero's are people too. We pay just as much attention to them, if not more than our loved ones
screw paying those bastards. im not going to become rich by paying for things.....

The problem is the Fiero flasher is it is before the switch so it has the fuse power on the input side all the time so the 3 tab with an added ground would be pulsing all the time. In order to use a 3 tab you would have to move the flasher to the other side of the turn switch so that power would be applied by the switch. That might be doable fairly easy though.

[This message has been edited by Dodgerunner (edited 06-18-2009).]

Has anyone adapted this technique to a 2-pin flasher unit yet? My Fiero has LED lights, and even with an electronic flasher unit, they blink really slow.

i guess the best thing to do would be to do the same as that guy did in the instructable... get the schematic info of the main IC and go from there. should be petty simple. find what voltage/resistance adjusts the blink rate and find out what more/less resistance does to it. im sure the rest of the circuit is to adjust for voltage coming in so the chip wont fry and to rais the voltage back up to drive the lights. of course a hazard flasher unit would require a bit more heavy duty circuitry to drive all the flashing lights at the same time.

Unfortunately, my knowledge of electronics is pretty basic. Re-pinning a few electrical sockets is one thing, but re-engineering an electronic circuit (especially not knowing how it works in the first place) will be pretty tough.

If I knew how the electronic circuit worked (and Ohms / Farads / etc values for the components), that would be a good start. Can anyone help with that?

take one apart and post pictures.

That can be arranged.

In the meantime, I saw mention of something that happens when there isn't enough current draw on the blinker circuit (with an electronic flasher unit). When the turn signal is in the "off" state, the light will still glow dimly. My turn signals are doing that. It is suggested that adding a resistor in parallel with the turn signal (to increase current draw) would fix it. I happen to have a few resistors of various sizes, so I think I'll try that.

Warning... resistor can get Hot... 1/4-1/2 watt resistor probably not work.
All LED forces to use resistor that is high watt... Ceramic or Al case high watt.
Resistor is low ohm... about 5-15 ohm. 10 ohm uses 15 watts at 12 volt. Needs 20 watt resistor and mount to metal.

Try LED source link in cave, LED marker.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)

my disability/retired pay needs to hurry and show its face! ill buy one to hack apart. im too lazy to go into my garage and dig under the dash for the right one in this heat.

I took a close look at the flasher unit in my Fiero. It's just a relay and a capacitor. The capacitor is wired into the coil side of the relay. I'm guessing the capacitor controls the "blink rate" of the relay.

Unfortunately, I couldn't find a μF rating printed on it. It does have a brand name and what appears to be a part number. Jamicon 732C2(K). I tried a Google search for that brand and character string, and came up with nothing.

Edit to add: there is a μF rating printed on the capacitor. YAY! I didn't notice it at first, because that part of the capacitor is butted up against the relay. It says 13V 1600 μF. I'm guessing a smaller rating (for example, 1200 μF) will make it blink faster?

[This message has been edited by Blacktree (edited 08-24-2010).]

hmm... that doesnt sound like any electronic flasher unit ive seen or heard of. it should have more than a cap and relay. maybe the goodies are inside the relay housing? think you can post some pics up of it?

It's marked on the package as an electronic flasher unit, recommended for use with LED lights. Although, I think the term "electro-mechanical" is more appropriate. The brand and model is Tridon EL12, sold in Advance Auto Parts. The funny thing is it works no better than the thermal flasher it replaced. Here are a couple photos.





As you can see, the guts of the relay are clearly visible. There is no circuitboard, no chip, no resistors... just a relay with a cap sitting next to it. The leads on the cap are soldered directly to the leads on the relay's coil.

EDIT TO ADD: OK, just read a bunch of complaints in other car / bike forums about the EL12 flasher unit not working well under a light load. So it looks like I need some resistors to increase the current draw, or a better flasher unit.

[This message has been edited by Blacktree (edited 08-24-2010).]

i guess ill hafta dig mine outta the car because i do believe they are different from that. i got mine at autozone (get in the zone!) for like 8.99. mine changed the blink rate from that god aweful non sequential slow blink rate to a more modern steady and a bit faster blink rate. ill get pics of the blinker unit and the speed they are at now... eeps, hooking up the battery on a motor swap with wires dangling... done it before, just gotta be super careful!

This POS flasher unit cost me about $13. If the one you have is better, and only costs $9, I'm all over that. Can you post a part number?

Yea after class today I can get that. I'll get pics of it all too. Maybe even get the hacking bug and chop it apart. Might even swing by Autozone for a pic of it in the package so you know exactly what to look for.

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First LX9 Fiero GT, 1987 | My Fiero Fuel Economy | MPG Display for OBD I
Youtube Videos of My GT | modernize your fiero with technology!
If you can't fix it with a hammer, you've got an electrical problem
Fiero's are people too. We pay just as much attention to them, if not more than our loved ones
screw paying those bastards. im not going to become rich by paying for things.....

since i seem to be getting so many PM's about my hitch, ill answer right here... i do not know where it came from, but it looks like The Fiero Store one. perfect for jacking the car, lifting the car and resting it on jackstands. 84-88 TRAILER HITCH

(Double Post)

[This message has been edited by Marvin McInnis (edited 08-24-2010).]

quote Originally posted by Marvin McInnis: (Double Post)

first post MIA....

I drove to the nearest AutoZone looking for a flasher unit ( got impatient... heh ). They had one 2-pin electronic flasher unit on the shelf, a Blazer FL32 (price was $9.99 + tax). It has a circuitboard inside, with a transistor and some resistors and stuff. Anyway, it works great! It has a nice steady flash, and blinks at a rate similar to modern cars.

BTW, sorry for the thread hijack.

[This message has been edited by Blacktree (edited 08-25-2010).]

its all good, it was subject related :thumbsup:

i have a different model from the one you got. i think there were three different ones iirc.

i started to want to tear into mine and modify the flash rate, but the IC is one of those tricky ones encased by the liquid drip casing and not a mold formed chip style with the ic number printed on it.

quote Originally posted by americasfuture2k: ... the IC is one of those tricky ones encased by the liquid drip casing ...

All I see is a relay, a resistor, an electrolytic capacitor, and a transistor... enough for a simple relaxation oscillator to drive the relay.

[This message has been edited by Marvin McInnis (edited 08-25-2010).]

the under side of the board with all the copper traces and the soldered leads... that black circle in the lower right is the ic. in the pic above it you can see a white circle with the letters IC in it. that is the opposite side of the board denoting exactly where that component is supposed to go. i didnt get pics of the relay all around since its just a resistor and 4 diodes. 3 N4004's and one... cant tell. its a zener diode

here is a better picture of it.. used the flash since its too dark to use natural light

[This message has been edited by americasfuture2k (edited 08-25-2010).]

didn't me and Archie talk about this a million years ago and we decided to go with an EL-12?

you need a *REAL* EL-12
not a replacement.

[This message has been edited by buddycraigg (edited 08-25-2010).]

a simple diode will keep the low beams on when the high beams are on. it can be had from radioshack. i dont remember what one it is. ill hafta get around to digging those out of a box.

quote Originally posted by Blacktree: I took a close look at the flasher unit in my Fiero. It's just a relay and a capacitor. The capacitor is wired into the coil side of the relay. I'm guessing the capacitor controls the "blink rate" of the relay. Unfortunately, I couldn't find a μF rating printed on it. It does have a brand name and what appears to be a part number. Jamicon 732C2(K). I tried a Google search for that brand and character string, and came up with nothing. Edit to add: there is a μF rating printed on the capacitor. YAY! I didn't notice it at first, because that part of the capacitor is butted up against the relay. It says 13V 1600 μF. I'm guessing a smaller rating (for example, 1200 μF) will make it blink faster?

Hey Blacktree, I see that you already have a fix, but to answer your question, yes putting a smaller value cap in that curcuit would speed up the rate. I used this exact flasher to fix a problem after puting sequential flashers on my Indy. The way it came was a little fast yet for me as the last light would barely get lit, if at all before it would restart the sequencing cycle. I ended up marking the cover where the cap was, drilled a hole to allow the cap I added to poke through the top, popped the cover off and put the added cap in parrelel with the first. I don't remember the value I added, but it worked perfectly by slowing it down to the speed I needed.


Kevin

[This message has been edited by Lambo nut (edited 08-25-2010).]

very interesting. isnt there a variable capacitor?

Did you mean variable resistor? You will not see a variable cap in this case as they are very large except for vary small trimmer caps which would be useless in this application.

quote Originally posted by buddycraigg: that page is 404.

Hmmm ... PFF used to be able to find old threads after they had been moved to the archive. Oh, well ... see this thread.

quote Originally posted by americasfuture2k: a simple diode will keep the low beams on when the high beams are on.

You don't need a diode; a short piece of 16 AWG wire will do an even better job of it. (I don't know whether Radio Shack even stocks wire any more, since it doesn't conform to their current "cell phones and toys" business model.)

quote Originally posted by americasfuture2k: ... that black circle in the lower right is the ic.

You may be right, but I'll bet that if you were to peel up that black dot you would find nothing there but circuit traces.

[This message has been edited by Marvin McInnis (edited 08-25-2010).]