Hacking the flasher control Module? Electrical Gurus needed.

[DJ Raydiate]

So, as some may know, I plan on fully customizing my tail lights next year to LEDS. Once I do, I know that I will have a hyper flash from the flasher control module . I saw the hack that AZDave did to his module http://www.rcaz.com/rcaz/sub%20indexes/turn_signal_flasher/DSC01482.htm and it got me thinking; what if one were to instead of replacing the wire loop with a longer length of wire, put in a potentiometer instead. That way one could change the resistance anytime one does a lighting upgrade in the car via pot vs having to pop open the module and mess with it every time. In theory, it should work right?

It also got me thinking that one may be able to change the actual speed of the flasher unit itself. Using a pot on two of the resistors and replacing the capacitor with a variable capacitor, one should be able to fine tune the way the module flashes.

If anyone has any input int this, it is very welcome because I would like to know what some of the more experienced people think of this; pros, cons, anything.

 

[motomattx]

Well the only variable capacitors are used as tuning capacitors in the r/c tank circuit for old style turn to tune radios and they are decently big and dont come in a good assortment of ranges for the most part. All that you have to do is use a "load equalizer" like they use on motorcycles that have led rear kits.

 

[DJ Raydiate]

Actually there is a wide assortment of variable capacitors on the market now. A load equalizer is just a band-aid fix for most people. Not to mention that they are heaters and would get extremely hot in stop n go traffic due to the fact that the brakes run off of the same circuit. If I was simply doing the pnp led bulbs, I'd do the band-aid fix but beings I am doing custom led arrays in the tail lights, hacking (fixing) the flasher module is the better option. At this point, getting rid of the hyper flash is more important than controlling the flasher itself.

 

[brads]

You should be able to get a resistor load sized big enough that it doesn't get too hot. But I agree that they are a messy fix.

Your thoughts about using the pot to tune it has one issue. Usually the wattage rating on a pot indicates the max wattage(and current flow) at the max resistance value. So if you back calculate the max current from the max resistance and the wattage rating, you will see most pots aren't good for the amps you want. A few trial and errors with 18 gauge wire length might be the better option.

 

[DJ Raydiate]

That's what I was kind of afraid of. I know that 6" 18ga wire will fix the hyper flash when I do the tails because I will have about the same amount of leds AZDave had. I just didn't want to take it back out and play "guess the length" when I do the front and side markers. I might just take the unit and move it to the glove box if that is the case.

 

[luv2rallye]

Ya a pot to carry the amps you need without damaging itself (and at around an ohm) would be the size of a grapefruit (or larger if it's a carbon pile used to test batteries) and be very expensive.

 

[motomattx]

Yes, it would .

 

[DJ Raydiate]

Yeah I was thinking that there has to be an easier way to hack the box than the wire trick. I have seen other ways to hack other boxes. One way was to disable the hyperflash pin on the ic. Others were to add a pot or go with a different resistor for the one going to the pin on ic for the hyperflash.

 

[motomattx]

It would be much easier to create an entire new module to flash the led's.

 

[brads]

That's what I was kind of afraid of. I know that 6" 18ga wire will fix the hyper flash when I do the tails because I will have about the same amount of leds AZDave had. I just didn't want to take it back out and play "guess the length" when I do the front and side markers. I might just take the unit and move it to the glove box if that is the case.

If you calculate the resistance on that 6" section of wire, and the use the current flowing through it, you could come up with a voltage value. Then when you have a new current level(as a result of switching more lights to LEDs), you just use the new current, the earlier calculated voltage, and come up with a target wire resistance... It might not be exact but it'd be a good starting point.

 

[91-GS]

Agree with motomattx. It would be easier to build a new flasher unit. That way you can have adjustable flash speed. Or even adjustable "on" and adjustable "off" time, if you so desire.

 

[estoyaqui30]

If you calculate the resistance on that 6" section of wire, and the use the current flowing through it, you could come up with a voltage value. Then when you have a new current level(as a result of switching more lights to LEDs), you just use the new current, the earlier calculated voltage, and come up with a target wire resistance... It might not be exact but it'd be a good starting point.

I was thinking along those same lines. take a 6" piece of 18 AWG wire, measure the resistance. Calculate the load capacity of the 18 AWG wire based on the wire gauge and lets say 12.8 volts, you should be able to get an equivalent wire wound power resister and install it inside the flasher box. That's what I'm thinking. I got PnP "1157" LEDs from LED Lights, Bulbs & LED Lighting Accessories - SUPER BRIGHT LEDS and there are 2 in the rear and the one in front. I have the front and one rear in currently...if I put in the last rear, it won't even flash anymore.

 

[brads]

The only reason I suggest doing it off calculated values, is that measuring a low resistance like a wire can be tough to do accurately. Although in this case, the value isn't critical. The important measurement is the current, then you should be able to reduce the equations to a ratio of length and current, and solve that way.

 

[motomattx]

If anyone can give me a couple of good reasons to reinvent the wheel with the bulbs in the Dsm, I might consider drawing up a schematic for a led flasher unit, I cant really find one myself other than being bored and wanting led's for the sake of saying "hey look at my herra frush led's yo'"

 

[DJ Raydiate]

It would be much easier to create an entire new module to flash the led's.

I would do this but not everyone is going to want to make their own flasher units. I was trying to figure out a way that anyone with experience in soldering/de-soldering could hack the existing module.

If you calculate the resistance on that 6" section of wire, and the use the current flowing through it, you could come up with a voltage value. Then when you have a new current level(as a result of switching more lights to LEDs), you just use the new current, the earlier calculated voltage, and come up with a target wire resistance... It might not be exact but it'd be a good starting point.

Yeah that would work but it still requires one to pop the box open every time one does an upgrade to solder a new wire in.

If anyone can give me a couple of good reasons to reinvent the wheel with the bulbs in the Dsm, I might consider drawing up a schematic for a led flasher unit, I cant really find one myself other than being bored and wanting led's for the sake of saying "hey look at my herra frush led's yo'"

Well, I think there may be many reasons why one would like to upgrade to leds vs keeping their incandescent bulbs. I don't want to put a ton of money into my GS to go turbo or anything like that so I do little style upgrades to it. I didn't have to reinvent the door sills but I gave them some new style. I like the look of the leds in some of the newer cars and thought it would look good on mine. I don't need anything fancy in my tail lights but I am going to be doing little things to them. I already have the schematics for analog sequentials so I'm good.

I'm still trying to teach myself electronics so I'm learning something new everyday. That said, a pot would not be the way to go. However, I may have come up with something else to use. Upon reading last night about rheostat vs potentiometer, the rheostat would handle more current than a standard pot.

Talking with my Father-in-law who is going to school to get his associate in electronic engineering, he suggested that this may work in place of the stock wire loop to adjust the resistance to keep the hyper flash at bay.

 

[Blurred Talon]

Are you planning any 'light show' stuff with your LED tails? Sequential turn signals or the like?
If so you could have a separate controller to control what the lights do.

My tail lights are controlled via a micro controller.

 

[estoyaqui30]

I would do this but not everyone is going to want to make their own flasher units. I was trying to figure out a way that anyone with experience in soldering/de-soldering could hack the existing module.



Yeah that would work but it still requires one to pop the box open every time one does an upgrade to solder a new wire in.



Well, I think there may be many reasons why one would like to upgrade to leds vs keeping their incandescent bulbs. I don't want to put a ton of money into my GS to go turbo or anything like that so I do little style upgrades to it. I didn't have to reinvent the door sills but I gave them some new style. I like the look of the leds in some of the newer cars and thought it would look good on mine. I don't need anything fancy in my tail lights but I am going to be doing little things to them. I already have the schematics for analog sequentials so I'm good.

There are plenty of good reasons. Having LEDs doesn't need to be ricer Yo! If you can reduce the electrical demand on the alternator you would reduce the parasitic load on the engine and have more power, better throttle response and better fuel mileage (my car is a daily driver).

It's not bad in having such long life as the LEDs also afford. I'm talking PnP lamps assemblies from LED Lights, Bulbs & LED Lighting Accessories - SUPER BRIGHT LEDS. It would be nice not to have to pull the gauge cluster each time an incandescent lamp blows out.

 

[estoyaqui30]

That reply was meant for motomattix

 

[DJ Raydiate]

Are you planning any 'light show' stuff with your LED tails? Sequential turn signals or the like?
If so you could have a separate controller to control what the lights do.

My tail lights are controlled via a micro controller.

All I want mine to do other than normal function is the Sequential turns. I have the boards drawn up from the schematic via HIDPLANET. Other than that I will have them "Breathe" when turned off for a set amount of time.

I love your work btw. Have you overcome the hyper flash or am I reading too much into it?

 

[Blurred Talon]

Thanks, I need to be unlazy and finish my designs. I'm redrawing my boards again which is a PITA.
I didn't do anything, Talons have a flasher relay because they have independent turn signals. The Eclipse has the flasher module.

I know azdave did the flasher mod and then his sequential stuff was controlled via microcontroller.

 

[DJ Raydiate]

I see. I know Dave had the hack and then he went to microcontroller. My sequentials are going to be analog and I can control the speed that they fill the light but if hyperflash is present then it will not look right. I still haven't figured out how to design the boards. I will be taking a page out of defyant's book and doing them on lexan. I pmed him over on planet and asked if I should worry and he said no so.

I will be testing something out next Fri for adjustable resistance going to the module. Once I can find that sweet spot to where there is enough resistance present for the hyperflash to stay at bay, I'll take a reading and then place the proper resistor. I will be trying to figure out how much resistance is needed to fool the ic into thinking everything is in place and not cause it to hyperflash. I'll post my initial results and then the long term results.