Shadow7874

Kinda curious how hard it would be. Im an engineering student (although not electrical) and wouldnt mind making my own especially if it can be done cheap.

Does anyone happen to have a wiring schematic perhaps? Ive never seen the actual harnesses in person so i dont know what all there is to them.

ikemikestang

Cheers
http://iihs.net/fsm/?dir=40

JDWalton

I would think you can do it with a couple transistors and a few caps. First bulb would be direct, also parralel a cap feeding the turn on lead to a transistor that switchs in power to the second bulb and repeat that circuit for the third bulb with the sense signal comming from the second bulb. Probably do it for $20

Taskiss

just off the top of my head, two 556's, a couple of caps and resisters, 4 12A darlingtons and a piece of prototype board. Total cost, probably $8.00

Power up all three bulbs from the brake line but delay one and 2X delay the other. Repeat for the other side.

Look up "555 timer delay circuit", use the darlinglintons for switches, pot the whole thing in epoxy after you figure it out.

awakeinAZ

why would you?

Shadow7874

Why would i do something that costs ~10 instead of ~100?
Gee, i dont really know.



Thanks for the link and ideas, ill try and do a bit more research and see what i can do

Taskiss

by the way, the 556 is just two 555 timers in one package

Here's a circuit (the one on the bottom) that includes everything you need, just don't use variable resistors, use fixed ones.

http://www.eleccircuit.com/power-on-...rcuits-by-555/

Shadow7874

So would i just use the circuit number three and have one circuit for each of the three lights and change the timer to like 1 2 3? So that the first like would have x delay, the second would have 2x and the third have 3x
And how do you change the timing of the circuit?

Joolander

there's no need to be hostile, friend

Taskiss

You don't delay the center most light. THe next one over, you use 1/2 of the 556 timer in a circuit like #3 to set to 1/3 of the total time the light is on, then when the turn signal is on, it switches the darlington transistor on, and put the output of which goes to the center most light. The 556 is two 555's in one chip. Look up the pinout on google.

The other half of the 556 you build an identical circuit as the one controlling the center light, but you put the output of the switching transistor to the most outside most light after a 1 second delay. You have to use something big for the transistor, a light takes like 5 A when lit, a 12 A darlington transistor will do you just fine.

The delay is calculated with the value of the capacitor and the resistor. You play with those (see the timing calculation on circuit #1) to set them to what you want, changing resistor values to change the timing.

SO, put voltage on (by turning the turn signal on) and the center most light comes on, a half second later then next one, and a half second later the next.

THat's it for one side of the car, now, make an exact duplicate.

power goes on from the turn signal
light closest to the center of the car goes straight to the turn signal wire and it lights immediately
middle light, the signal wire switches timer #1 on after 1/3 duty cycle
outside light, the signal wire switches timer #2 on after 2/3 duty cycle
they all stay on the last 1/3 of the duty cycle

That's one duty cycle...one "blink" of the blinker. The next blink, it repeats...and so on and so forth, 'till the turn signal turns off and the power goes off