My customer has me building him a "street legal" drag car that has a custom racing steering shaft that has no provision for a turn signal switch nor any way to incorperate a aftermarket "truck style" turn switch kit onto it. My question: How do I wire up a working system from scratch useing a three way (three pole, center is off) toggle switch for the dash, four bulb wires (one from each corner of the car), a flasher and the one brake signal wire from the brake light switch. I have tried to draw out a schematic many times on paper but allways fail when it comes to incorperating the brake light . Please help me finnish this drag car so I can get paid. Mark Hand, Loomis Ca.

By the way its a 66 chevelle but has no exsiting stock wiring

i think you series the taillights together, and maybe use a momentary switch. you'll also need a relay and or a flasher, or he'll just have to manually push the momentary switch to activate the turnsignals

Everything you need, couple options http://www.ronfrancis.com/products.asp?dept=32

From scratch with your own parts:

Switch is labeled as flipped right or left
One flasher unit (silver can)

Bat Pos. ---> Flasher Can ----> R switch ---> R Stop Gnd / R Ft Sig pos / R Dash light
...................................----> L switch ---> L Stop Gnd / L Ft Sig pos / L Dash light

R Stop Pos to Brake switch
L Stop Pos to Brake switch

This will work on rear bulb sockets that have a separate ground from the housing (80's up). I use sockets from the front lights of dodge neons as they are compact and easy to get at the junkyard.

The switch pulls power through the flasher which causes the flash and by using the ground to switch the lights you are able to have functionality without more complicated wiring. When the switch is not active, it grounds the rear bulb to enable the stop light to work.

Note: i've used this on a few stripped hot rods, but bench test it to ensure your switch acts the same as mine have, as I've had a few that didn't work, but a different brand would

http://i272.photobucket.com/albums/jj185/2006CobaltLS/1967Chevelle4Dr/rodsignals.jpg

So these three are in parallel? R Stop Gnd / R Ft Sig pos / R Dash light

And the brake switch has to be normally grounded when not depressing the brakes?

And the L/R switch is normally grounded when centered?

I think I'm missing something.

Not sure what else is wrong with that diagram, and I think there is, just doesn't look right, IMHO, but no flasher is shown. Jim.

Andrew's diagram appears to be similar to the marker light circuit, which will flash opposite of the turn signal circuit due to the breaking of the ground instead of the power. And yes a flasher will need to be added into the circuit.

Normally without a circuit to cancel the stop lamp on the side that is calling for turn signal, the lamp will not flash with the brake on. Most have the circuitry in the turn signal switch, others use separate bulbs for the turn signal function.

oops, I did forget the flasher, it would be between the 12 v and the signal switch.

My parts:

Signal sockets from early 90s neon signal lights, three prong switch is a hardware store special (brass), brake light switch 60s GM truck, and the flasher is a standard two prong.

It is out of the ordinary to switch the grounds, but it is more common on newer cars and the front and rear signals are out of phase when the brakes are on and the signals activated.

Based on Left signal:
1-No brake lights, signals activated
12 v goes thru blue wire -illum bulb- ground through brake switch.
Front is standard 12v - bulb - Grd
They blink in unison
2-Brakes applied, signals activated
When flasher is open, 12v goes thru orange and grounds thru signal wire (flasher unit)
When unit flashes (closed) , 12 v goes to blue wire and bulb is no longer lit (0 V at bulb)
Front bulbs signal normally
3-Brakes applied, no signal
12v from brake switch to bulb, grounds thru signal switch

Philip has a great point. If there's room in the housing a separate bulb would be easier than my diagram. I used this in a housing with room for one bulb. (39 ford tear drop).

Flasher is also now in the awesome paint sketch.

The bulb if added to the same housing would need to be brighter then the stop lamp bulb to be seen.

An EE could probably design an LED circuit that would be effective at all 3 functions. Low lumen for tail, part of the LED's used to do a sequential motion in a higher lumen for turn and an inboard area that acted as the stop lamp. Somewhere around 50 LED's would be enough :D

you can't spell geek without EE

Sorry, don't want to sound like a jerk, but I still have a problem with that diagram. Where are the brake lights getting ground when the signals aren't on? Does it feed back thru the front signal and ind bulbs? Wouldn't that have to light those bulbs to get ground? I assume that's a 3 terminal SPDT switch, rests open in the center off position. Might work with a switch that rests at ground, if such a thing exists. Jim.

I think I would hide one of the available universal kits and hack in a couple of relays and a 3 way toggle to operate it remotely. Just remove the stalk and wire the relays across the contact points that it would normally 'connect'.

Where are the brake lights getting ground when the signals aren't on? Does it feed back thru the front signal and ind bulbs? Wouldn't that have to light those bulbs to get ground? I assume that's a 3 terminal SPDT switch, rests open in the center off position. Might work with a switch that rests at ground, if such a thing exists. Jim.

Andrew, I have this same questions. I don't see the grounds in the diagram. You've got three wire sockets, so I am assuming they are not grounding through the shell. But where are the switch grounds, in the center off position?

I'm liking the look of where this is headed, not trying to be cynical, just trying to figure it out.

A circuit will seek a ground and use what ever it can find. It is why most weird electrical problems are bad grounds. In this case the rear lamps will use the grounds on the front lamps to complete the circuit. It is the same type of circuit that allows the side marker lights on newer cars to flash opposite of the turn signal, it is using the ground from another circuit, in this case the turn signal.

I have a race car and plan on putting an electronic one made by Speedway. Its really simple to wire up, and is a push button with auto cancel. Its really not that expensive, sells for around a hundred bucks.

The bulb seeks ground through the switch, as the three way switch I used grounded out the circuits when not in use. Not all switches do this, but I happened upon a few that do and didn't notice the difference until now when ya'll brought it up. If I was close to the rod I would look up the part number but california and south dakota are a ways apart.

A circuit will seek a ground and use what ever it can find. It is why most weird electrical problems are bad grounds. In this case the rear lamps will use the grounds on the front lamps to complete the circuit. It is the same type of circuit that allows the side marker lights on newer cars to flash opposite of the turn signal, it is using the ground from another circuit, in this case the turn signal.

I agree with that. But I don't believe we should be doing, recommending on TC, wiring that works without intent. To me, that's bad design, like saying "bondo it". The pint that new cars work with flashers out of phase is a good one, but that is by design, not by a circuit finding its own ground.

The bulb seeks ground through the switch, as the three way switch I used grounded out the circuits when not in use. Not all switches do this, but I happened upon a few that do and didn't notice the difference until now when ya'll brought it up. If I was close to the rod I would look up the part number but california and south dakota are a ways apart.

So if I'm following correctly, what the diagram doesn't show is a ground path to through the switch. But the switch you are using has this feature. I feel better now!