My sedan (avatar) uses a 1940 Ford column with an old style turn signal switch that clamps on the column and does not have a hazard lights function. In order to have hazard lights (4 way flashers) I installed a 4 Pole Dual Throw heavy duty toggle switch I bought off Amazon, as shown in the picture below. The switch is a selector switch with either the ON or ON position (no center OFF position). It has 12 terminals on the back. The four center terminals connect to the four upper terminals in one switch position or the four lower terminals in the other switch position, as shown in the image below. I made a bracket to mount it up under the dash where you don’t see it, but it’s easy enough to reach. In one position the turn signals function normally. In the other position the hazard lights flash. I wired it as shown in the image below. So you can use the older style turn signal switch without the hazard function and still have hazard lights. Here is the switch description for the one I purchased (there are probably several that will work). I have no interest in Amazon or the company that sells these. Hope this helps someone. hot rod dan
Yep- I can see them now. So in your setup a single flasher is used for hazards and signals, instead of a separate flasher for each?
Sorry I wasn't clear. Two flashers are needed. In effect you splice the wires going to the turn signal bulbs as shown in the 3rd image if your car is already wired and add the red wire & flasher shown in that image.
So, I assume that you have separate brake lights from the turn signals? If you don't, this 'shuts off' the brake lights when operating as hazard lights. To fix that, run an additional wire from the brake light switch to the 4P2T switch on the hazard side. This will cause all four lights to light up when the brakes are applied (rather than flash), but you will have brake lights...
Thanks for this - saving it. Will work great for me in the UK where we have to have separate brake lights.
That's really neat; you could also put one of those aircraft switch covers on it if you needed to install it on the dash.
Steve, Not sure I get that is a problem. Any older common emergency flasher system I have seen uses the brake light filament for the flasher function. Common older direction signals also use the same filament for turn signal and brake lights....so I see no downside to the OP's method. The exception may be more modern vehicles that use separate filaments for brake and directional function, with amber for directional and emergency flasher. Am I missing something here? As an aside, I did a similar system to wire a vehicle for lights when being towed. Rather than auxiliary lights, I wanted to use the vehicles rear lamps but operate them from a trailer wiring connector. I used a 3 pole, double throw switch arranging the vehicle lamps to the center row terminals, the trailer light source to an outer set of terminals, and the vehicle light wiring to the remain set of outer terminals. Essential just like the OP's system but for the source of input. Also used a switch guard to prevent unintended light isssues. Ray
If the brake/turn use the same lamp filament, when he switches to 'hazard' he's taking the whole turn signal switch out of the circuit, including the brake light circuit; ergo no brake lights. Running a separate feed from the brake light switch to the hazard side of the switch will 'defeat' the hazard flashers only when the brake pedal is depressed giving you brake lights. A side effect is all the other 'hazard' lights come on solid while the pedal is pressed, but you have brake lights. This is how some of the OEMs did it on the early 4-way flasher circuits of the '60s/70s.
I usually don't drive with the hazard function on. I usually use the hazard function when the car is parked and I'm working on it.
If I come up behind someone with emergency flashers on, the LAST thing I do is tailgate 'em... Emergency flashers indicate they may have a problem 'keeping on keeping on'! Like a 'hazard'...
The Jalopy Journal
