Hazard (4 Way) lights and Signal lights separate relays

[RonJ]

Having studied the various offerings and subsequently purchasing a 22 Circuit Speedway aftermarket wiring harness (91064022) a question came up that someone may have solved.

It seems all aftermarket harnesses have a separate relay (flasher) for the Hazard lights and for the Signal lites.  For safety reasons the Hazard lites are on their own circuit fuse and relay which is powered constant hot.  The position of the key is not a factor.

The signal lite relay is powered from a switched line that is hot when the key is in the ON position.  The harness I purchased was a customer return, new and unopened, sold at a discount that came with a plug for GM steering columns.  Others come for Ford or Universal.

That is of no concern because the plug be can be removed or in the case of the Universal it can be wired any way you choose.  Unless I’ve missed something it seems that the aftermarket harnesses are designed for turn signal and hazard switches that are set up for the separate relay system including the separate hazard switch as found in modern vehicles.

However all the aftermarket turn signal switches (7 wire) do not have provision to utilize the Hazard flasher separately from the Signal flasher.  It seems it’s the installers choice as to which feed to the unit is used either the switched or the unswitched, but it is either one or the other.

 

The question is:  

Is there an aftermarket turn signal switch that is made to utilize the Signal Flasher when signalling but uses the Hazard flasher when used in an emergency, or is there another solution?

 

 

 

[Happy 46R]

Hi Ron,

Not sure I understand the question. It is my understanding that you cannot use the turn signal device to activate all four turn lights at the same time. This is done through a seperate relay and switch. The 4 way flasher and relay can be wired back into the turn light wiring or relay but to activate the four lights together a second switch /flasher and relay are required. Not sure if this will help your question or not: https://www.youtube.com/watch?v=lnhMx-fnUmI   Let me know if I missunderstood or if this helps.  Dave

 

[allbizz49]

Just don't add hazards. 

[Sniper]

Hmm, I rewired my 51 with that kit and my hazards work as well.  I do recall having to take apart the aftermarket turn signal switch to sort out how it was wired and how it worked.  Cleaned it up and lubed it too.  But I'll be danged if I remember having to do anything special to get it to work other than that.  I google the switch hoping for a schematic, which I did find but it didn't match what I had.  I might have the details in my notes somewhere.

 

I will tell you the T/S switch originally used one flasher to do both jobs and I probably left it like that.

 

The only reason to use a separate flasher for the hazards would be to allow them to be used with the key off.  I don't know if that was a change in the safety regs at some point, but from a functional standpoint you can use one flasher for both jobs, except no hazards with the key off. 

Edited February 11, 2023 by Sniper

[RonJ]

For sure, back in history a single flasher was the only one in the circuit and it did both jobs, turn signal and hazard.  In my collection of “stuff” I have a Do-Ray Flash-All 999 turn signal switch designed for older vehicles.  It a 4 wire unit with indicator as well as Hazard function.  Move the lever up or down for Signals and pull it out for the Hazards.  It works very well considering the Patent is 1964.  
The Red wire is from a two prong flasher (Purple in the harness), Green goes to right signals, Yellow to left signals, Black to the indicator in the switch.  This unit was originally designed for a three prong flasher that had the P terminal for the indicator light, but the Speedway harness is designed for a two prong flasher so I added a couple diodes - see diagram and the indicator works well.  The case is ground.

As above I could just not have Hazard lights but this particular switch has the function so I’d like to use it.

I could also live with wiring it to the switched by ignition flasher relay (Purple in the harness) or the always hot Hazard relay (brown in the harness).

The relays themselves are identical and I have tested it both ways and it works well.

I could live with it either way but it would be much better for safety having it work as in my first post.  I looked at the internal connections of the Flash-All to determine if adding a wire to the circuit for the hazards is possible but it is all riveted and I would prefer not to disturb it since it serves the purpose for safety certification.

I have considered ordering one of the 7 wire units on the market that have the Hazard and Signal function as well as the indicator but I thought I would ask my initial question if a unit was already available for separating them or if someone has modified one.

Without having a 7 wire unit in hand to see the internals I’m wondering if it could be modified by adding a wire to use the feed from the hazard relay for that function and leave the design feed for the flasher function.

For those that are wondering why am Ingoing through all this effort I’ll post the applicable sections of the standards.

[RonJ]

Here’s the diagram showing the diodes and Speedway wiring.

[RonJ]

Here’s the applicable sections from the regulations.

Note it also says the turn signal switch must be self canceling but I may be able to have that not apply since the units aren’t available with that feature.

I know this opens the whole controversy of what is required for vintage vehicles.  My intent is simply to make my 47 as safe as possible.

The second column is the Fail conditions.

 

[RonJ]

Thanks for the YouTube link.  It is very informative.  I found circuit diagrams utilizing two relays and a single flasher online as well.  
The signal switches, either four wire or seven,  performs the function of the two relays in the video.

I am trying to use what’s already configured in the harness with separate flasher relays, one (Hazard) that is always hot, meaning will work no matter the key position and one (Signal) that is switched on by the key.

[DJK]

On 2/11/2023 at 6:41 AM, Sniper said:

Hmm, I rewired my 51 with that kit and my hazards work as well.  I do recall having to take apart the aftermarket turn signal switch to sort out how it was wired and how it worked.  Cleaned it up and lubed it too.  But I'll be danged if I remember having to do anything special to get it to work other than that.  I google the switch hoping for a schematic, which I did find but it didn't match what I had.  I might have the details in my notes somewhere.

 

I will tell you the T/S switch originally used one flasher to do both jobs and I probably left it like that.

 

The only reason to use a separate flasher for the hazards would be to allow them to be used with the key off.  I don't know if that was a change in the safety regs at some point, but from a functional standpoint you can use one flasher for both jobs, except no hazards with the key off. 

On my 52 with the Signal Stat 900, the 4 ways and turn signals both function with the ignition off and of course with ignition on.

[Sniper]

I have a PM 500, I had to go out and double check but neither work with the key off.

[Los_Control]

I have a sigstat 900 .... not working worth a crap right now   ?

 

[DJ194950]

Some installation required- see instructions.

 

?

[RonJ]

My United Pacific 5007 turn signal switch arrived.

It was chosen because it is of metal construction and the product photos showed it had screws for assembly for a possible modification to separate the Hazard and the Signal circuits.  Other switches that looked like this but were knockoffs since they were plastic did not show screws.

 

As promised here is the simple modification.

The Speedway 22 circuit harness has two flasher relays one for the Signal lites and one for Hazard lights with each having its own wire to go to a signal switch.  The UP5007 only has one feed wire from the Signal flasher to control both the Hazards and Signals.

see photos.

The Hazard function in the UP5007 is on its own little contact card which slides over the back of contact card for the Signal function.  The pencil shows the source for the power for the Hazard lites.  It slides on the contact pad with the black wire on it which is fed from the “L” contact on the Signal flasher which is energized only when the ignition key is in the “ON” position.

Luckily the modification is quite simple.

Flatten that contact the pencil shows and drill a small hole 3/32” for a new wire to pass through to be soldered.  You can skip the drilling and just solder the wire on that pad but good practice is to have a good mechanical connection before soldering.

Solder the new wire to this this location.  This wire will be fed from the “L” connection on the Hazard relay which is always energized.

The clearance is adequate that this joint won’t touch the pad the black wire is on but both can be covered with insulating tape for additional insulation.

A photo shows the pad covered.

Now when the Hazard switch is pulled it applies the voltage from the new wire to the 4 contact pads to feed the lites on each corner of the car.

When feeding the new wire through the sleeve containing the other wires leave a 3/4” loop right by the entrance to the switch to allow for the in/out movement of the Hazard switch 

Reassemble and test.  Everything should work as originally designed.

I am now using this UP5007 instead of the Flash All 999 in my first test.

[RonJ]

Due to file size the photo showing the modification was omitted.

Here it is.

[RonJ]

Just a final note.

I made this modification for personal use only and have provided the information for general interest.  
I’m not endorsing, encouraging, or recommending this modification.

Do what you wish with this information at your own risk.

Feel free to ask questions.