How to Add Turn Signals and Wire Them Up

Want to add turn signals to your hotrod?

You should! It's not that hard...

You have 3 options:

1. Use a factory switch.

2. Use an aftermarket switch.

3. Make your own switch system. (It's easy!)

Factory switchMost of you will have a hotrod that uses a steering column that has a turn signal switch built in. What you need to do is find the wiring diagram for the vehicle the column came from. Just find it on the internet. It will show you which wire should go where...

Aftermarket switch

Some of you will have a hotrod that doesn't have a factory switch in the column.

The easiest way to add on turn signals without a factory switch is to use an aftermarket unit like these universal types:

aftermarket turn signals

You can get them at places like Napa or here:

However, some people don't like the look of it so they want to hide it. It's easy to put that unit under your seat, by the shifter, etc.

Make your own switch!

Still others would like to run their turn signals with a simple toggle switch on the dash.

There are two ways to wire it in...

-Wiring in turn signals that have their own seperate rear bulbs.

-Wiring in turn signals that share the rear bulbs with the brake and tail lights.

Let's start with the first... What you will need is a toggle switch and a flasher unit. For the toggle switch you will need a SPDT (Single Pole Dual Throw) toggle switch. They look something like this:

SPDT switch

They work something like this:

SPDT wiring

You can get them at places like Napa or here:

Next you need a 2 pin flasher unit. They look like this:

2 pin flasher unit

You can get them at places like Napa or here:

NOTE: If you want to run LED lights or bulbs, you will have to run an electronic flasher unit.

You can get them at places like Napa or here:

Now, wire them in like this:

turn signal wiring 1

Ok, now to wire in turn signals that share the rear bulbs with the brake and tail lights, you have to get a little creative... What you have to do is make the brake light wires and the turn signal wires combine in a way that the turn signal wires can override the brake signal. There are complicated ways to wire in multiple relays to do it, and aftermarket units that will do this but there is an easier way...

A quick and cheap way that works just as good is a tail light wiring converter for trailers. They will combine the brake wiring and the turn signal wiring so they will work.

They look like this:

tail light converter

You can get them at places like Napa or here:

Some have the tail light wire running through them (4 wire into 3 wire), and some don't (3 wire into 2 wire). It doesn't make any difference, as the tail light wiring isn't affected. All you're worried about is the brake and turn signal wires.

Note: Don't try to run them with LED's. The converters aren't made to run the extra voltage. Just stay with regular bulbs and it will work great.

Now wire it in like this. (This version uses a 4 wire into 3 wire converter. For a 3 wire into 2 wire converter, just take the tail light wire past it.)

turn signal wiring 2

Hey, what about hazard lights?

No problem, you just need another toggle switch and flasher unit. The toggle switch is different than the other though...

For the toggle switch you will need a DPST (Dual Pole Single Throw) toggle switch. They look something like this:

DPST switch

They work something like this:

DPST wiring

You can get them at places like Napa or here:

Now you need another 2 pin flasher unit.

Now wire them in like this:

hazards wiring

There you go!


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Return from Turn Signals to How-To-Build-Hotrods

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