Wiring the Hazard Circuit

[azbruin]

I've just about finished my wiring diet and think I understand how everything I need works. I didn't keep the hazard switch on my "88 donor and the only replacements seem to be turn signal switches with a hazard button. These are ugly and duplicatice since I have the original turn signal/headlight hilo switch. My only issue is that the turn signal circuit passes through the hazard swich and is opened when the hazard swich is closed. I can separate the two circuits but I'm not sure what happens if both circuits are closed simultaneously. Has anyone else resolved the issue? Is there an aftermarket solution?

[Gale K]

Hi AZ,

I dieted my donor harness, but I left the stock hazard switch buried up under the dash to initiate the hazards. However, I stared at the wiring diagram for a while, so I am pretty familiar with it. I will have to look at my wiring diagram when I get home, so take this with an initial grain of salt. :) To answer your question, "what happens if both circuits are closed simultaneously," I would imagine you'd get hazards running on all lights. If you feed power to the hazards to the front and rear, all lights blink. If you feed power to just turn, then whichever side you choose blinks (if you're not backfeeding the other side). If you feed both hazards and turn at the same time, I would imagine you would probably get hazards. It might (depending on how you wire the flashers in) blink both on the hazard and turn flasher. And the backfeed to the other side on the turn circuit through the hazard line. So, hazards flashing, turn flashing on one side and backfeeding to the other side.

You could control backfeeding with diodes. I had to do this as I am using a single toggle switch to feed turns, and it would backfeed through the hazard line on turn.

All that to say, I think it would probably be fine. Control the backfeed, and you're off and running!

[azbruin]

Thanks. I wired up just the turn signals today, separating the circuit from the hazards, and they worked fine. Haven't got to the separate hazards yet.

[FFinisher]

Here is a way it can be done, this is being discussed on the other forum as well. This drawing is pretty crude... I am no artist.

http://img232.imageshack.us/img232/6307/directionalschematic.jpg (http://imageshack.us/photo/my-images/232/directionalschematic.jpg/)

[lilnuke]

My solution was to use a hazard switch that I liked from another vehicle. In my case, I used a round one from a Honda S2000. I got the EVTM diagram from the dealer and wired it in. Not original looking, but works for me. You could use a switch from about any vehicle.

The turn signal and hazard power run through the switch (like the Mustang) and the turn signal power is isolated when the hazards are on.

http://imagehost.vendio.com/a/25056747/aphotoalbum/100_1460.JPG

[Norm B]

There are hazard switches available that remove the requirement for diodes and a second flasher unit. Bought a rocker switch type for a VW off of ebay and will hide it under the dash. In the normal (hazard off) it connects the flasher to the hot in run fuse for signal lights in your fuse box. When you switch on it does three things. It connects the flasher to the hot at all times fuse for hazards in your fuse box, it connects the flasher to the lights, and it connects the left and right signal circuits together.

The switch cost me $10 and shipping was free. Hooked it up to my wiring harness on the bench and it worked fine. Was going to include a diagram but I'm not that good with computers. Let me know if you really want one and I'll give it my best shot!

Norm