View Full Version : hazard light switch?
tcsracing1
10-11-2017, 06:02 PM
What is everybody using for their hazard light switch?
I need something 4 pole.
Gumball
10-11-2017, 07:41 PM
Lucas OEM style blade with two-position rocker (on/off).
alv69
10-11-2017, 07:55 PM
use a on off switch with diodes on the two wires going to the lights.
phileas_fogg
10-12-2017, 08:07 AM
I used an ON-[OFF]-ON dual pole, dual throw switch. It has 6 spade connectors on the back (if you've got a complete kit there should be one included). Connect power to the bottom spades and your indicators to the middle spades (each side gets one spade). With the switch in the bottom position, nothing is connected and so everything stays off. With the switch in the upper position, the connection is made and the indicators flash.
The dual pole means you don't need any diodes. If you use a single pole single throw switch like alv69 then you will need the diodes.
John
weendoggy
10-12-2017, 09:39 AM
I used an ON-[OFF]-ON dual pole, dual throw switch. It has 6 spade connectors on the back (if you've got a complete kit there should be one included). Connect power to the bottom spades and your indicators to the middle spades (each side gets one spade). With the switch in the bottom position, nothing is connected and so everything stays off. With the switch in the upper position, the connection is made and the indicators flash.
The dual pole means you don't need any diodes. If you use a single pole single throw switch like alv69 then you will need the diodes.
John
If you only use ONE signal indicator lamp, you will still need diodes, even with a DPDT.
phileas_fogg
10-12-2017, 01:52 PM
If you only use ONE signal indicator lamp, you will still need diodes, even with a DPDT.
Yep. Silly me; I just assumed a pair of indicator lights. My bad.
John
broku518
10-12-2017, 03:45 PM
I thought that the switch would be included. Hm, wonder what else I will need.
(ordered MK4 complete kit)
edwardb
10-12-2017, 04:59 PM
I thought that the switch would be included. Hm, wonder what else I will need.
(ordered MK4 complete kit)
A double pole toggle switch is included with the complete kit. As are all the other switches, e.g. turn signal, high/low beams, horn, headlight, ignition, etc. Not everyone chooses to use them, therefore the different answers you're getting here. Many want Lucas style switches, for example, which is different than the supplied hazard toggle. Plus Lucas doesn't make a double pole, so it's necessary to do the diode approach if that's what you want.
broku518
10-13-2017, 08:52 AM
Thank you edwardb.
tcsracing1
10-20-2017, 07:13 PM
thanks guys. I will order another wiper switch will make it simple to use it as the hazard light switch.
edwardb
10-21-2017, 12:48 AM
thanks guys. I will order another wiper switch will make it simple to use it as the hazard light switch.
Do you mean the Lucas style wiper switch? Not sure that's a good candidate for a hazard light switch. The terminals being switched are specific to the Lucas wiper motor including a park function.
cnutting
10-21-2017, 08:41 AM
If you only use ONE signal indicator lamp, you will still need diodes, even with a DPDT.
Sorry if this is a silly question, but can you explain the diode installation? I'm having some glitchy behaviour with my hazards using the 289 rectangular led tall lights.
Boydster
10-21-2017, 08:57 AM
Sorry if this is a silly question, but can you explain the diode installation? I'm having some glitchy behaviour with my hazards using the 289 rectangular led tall lights.
The idea of it is to bring all the lights together when being controlled by a single pole hazard switch, but have them separated to the sides when using the turn signal switch.
So here is how you'd wire a hazard single pole switch vs a double pole switch. Credit for the drawing to 427sc.
75703
I used 5A 30V Shottky diodes and it works very well.
cnutting
10-21-2017, 09:24 AM
Thanks for the info. I currently have a double pole switch. The issue I'm having is the rear hazard lights only function if the brake switch is active. Turn signals work fine, fronts work fine for turn and hazard.
edwardb
10-21-2017, 09:44 AM
Thanks for the info. I currently have a double pole switch. The issue I'm having is the rear hazard lights only function if the brake switch is active. Turn signals work fine, fronts work fine for turn and hazard.
That's a wiring or bulb issue of some kind. Almost for sure not because of the switch, diode use, etc. The +12V for the hazards comes from one source in the harness and is supplied to all four corners through the flasher. So if the fronts are working and the rears aren't (and interacting with something else like the brakes) that's a different issue. Check (1) that you have the wires routed correctly to the proper bulb elements in the rear lights, (2) that the bulb is installed properly. It's possible to get the 1157 bulb into the socket improperly and contacting the wrong terminals.
cnutting
10-21-2017, 11:07 AM
Thanks for the response. Couple more pieces of info, one is I'm using the trailer hitch converter and the tail lights are led, but the fronts are standard filament 1157. So... I'm thinking either the mismatch in bulb types might be causing something due to differing resistance (or some other electrical hocus pocus), or I'm feeding the wrong leg of the taillight. I think this is along the lines of your suggestions.
Thanks for the response. Couple more pieces of info, one is I'm using the trailer hitch converter and the tail lights are led, but the fronts are standard filament 1157. So... I'm thinking either the mismatch in bulb types might be causing something due to differing resistance (or some other electrical hocus pocus), or I'm feeding the wrong leg of the taillight. I think this is along the lines of your suggestions.
Did you change your flasher module to be compatible with LEDs? If not, that's your problem.
edwardb
10-21-2017, 05:47 PM
Did you change your flasher module to be compatible with LEDs? If not, that's your problem.
I doubt that would be the problem. Front and back use the same single flasher. If the fronts are flashing, there's enough resistance for the rears to work as well.
cnutting
10-21-2017, 06:45 PM
I doubt that would be the problem. Front and back use the same single flasher. If the fronts are flashing, there's enough resistance for the rears to work as well.
Yep, everything flashed correctly, so I'm confident all the components work.
I am using the led flasher. Just for giggles i tried the regular one and same issue.
Big Blocker
10-22-2017, 01:38 PM
Sounds to me like you have the rear "Hazard" feed connected before the brake switch, hence the brake switch needs to be activated to allow power flow to the rears . . .
Check your wiring splices between the two different sources to the rear - one is Brake power, other if Hazard power.
If the Hazard power is connected after the brake switch, it will allow current flow to the rear, without needing to press on the brake pedal.
Also, FWIW, it's the flasher that needs to see resistance, not the bulbs. They create the resistance. LED's don't provide enough resistance to cause a "normal" (thermal) flasher to function.
If you have at least two bulbs that are incandescent, your LED's attached to the system should work fine (the incandescents are providing enough resistance to activate the flasher).
If not, then a dedicated LED flasher is required.
Doc
cnutting
10-22-2017, 06:39 PM
Interesting Doc. I'll go back through the schematic and my notes to see how I actually did it.
tcsracing1
10-23-2017, 10:28 AM
Do you mean the Lucas style wiper switch? Not sure that's a good candidate for a hazard light switch. The terminals being switched are specific to the Lucas wiper motor including a park function.
it looks like it worked for phileas_fogg
edwardb
10-23-2017, 11:29 AM
it looks like it worked for phileas_fogg
Unless I'm missing something, he described an ON-[OFF]-ON dual pole, dual throw switch. Not the Lucas wiper switch. Same number of terminals and looks similar, but not the same thing. The wiper switch is [OFF]-ON-ON and the terminals are specific to the wiper park-low-high functions.
It's super easy to wire the hazards with an ordinary SPST switch and diodes and shown by Boyster in post #13. There are an unlimited number of SPST switches and styles available.
phileas_fogg
10-23-2017, 01:38 PM
Edwardb is correct; I used the dual pole, dual throw switch provided by F5 in their complete kit.
Boydster
10-23-2017, 04:46 PM
Considering you used a trailer light converter, and the rear hazards only function when the brake circuit is active... the converter controls both of those functions... so I'd be looking at a failed or mis-wired converter. Also, make sure your converter is OK for use with LED's. Many are not.
cnutting
10-23-2017, 07:12 PM
Thanks Boyd. I've been over my schematic and notes and it seems to be heading in that direction. Time to crawl under the dash...
I assumed that since the converter and led tail lights came from FFR that they would be compatible, but we know about assumptions...
Sorry to the OP for the thread hijack...
cnutting
11-04-2017, 11:47 AM
Did several tests and it all circles around the converter. This unit takes three wires in; left signal, right signal, brake and two wires out; left and right. This wiring is correct.
Today I removed the dpst switch and connected the left signal wire to the pink wire from the hazard flasher, all good. I connected the right signal wire to the pink, all good. As soon as I connect both, no tail lights flashing, just the fronts. Step on the brakes, everything works.
Something about both wires flashing (at the same time) without the extra juice from the brake wire seems to throw the converter off, but I don't have a schematic for that unit so not sure what is happening inside the magic box.
Hate to throw parts at it without knowing the root cause....
cnutting
11-11-2017, 03:57 PM
Fixed the problem. Short answer- the provided converter isn't compatible with LEDs. I'll post a more detailed remedy in my build thread later...
tcsracing1
07-16-2019, 08:08 PM
what switch would be period correct in a cobra?