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How to separate brake lights from turn signals on a '70 Impala

2.6K views 12 replies 7 participants last post by  Elderodder  
#1 ·
On my '70 Impala, I want to separate the brake lights from the turn signal (and 4-way flasher) lights, so I can have amber turn signals, and also so I can have brake lights and turn signal showing at the same time. I also want to have the 4-way flasher amber.
I have taken a first look under the dashboard, it is very tight under there, as big as the car is! I cannot really see much of interest, especially since I do not really know what to look for; all I have noticed is that the brake switch (at the brake pedal) has 2 wires, one white and one orange.
So, how can I do that?
Thanks!
 
#2 ·
This is hard to understand. First off if you were talking about Amber turn signal lights on the front just change out the bulbs to Amber bulbs. Second issue is that without fully understanding the wiring for turn signals and brakes trying to rewire the logic in the switching you're in for a nightmare it's rather complicated.
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#3 ·
This is hard to understand. First off if you were talking about Amber turn signal lights on the front just change out the bulbs to Amber bulbs. Second issue is that without fully understanding the wiring for turn signals and brakes trying to rewire the logic in the switching you're in for a nightmare it's rather complicated.
It looks like the OP resides in France, and I'm pretty sure he wants to convert to the Euro standard of separate turn signals/brake lights on the rear, in which case the turn signal lens is amber and the brake is red. Some US spec automobiles actually came this way back in the 80s and 90s, so it's not unheard of. The greater concern (for me, at least) is the modifications required to the taillights themselves; the OP would need taillight assemblies with separate and or additional filaments/bulbs for each function AND the proper colored lenses (if they are even available). Otherwise he would need an additional wire run from the brake switch to the taillights, and some wiring mods at the brake switch/turn signal switch to isolate the brake circuit from the turn signal circuit.

I'm sure it can be done, and may be required in order to register and operate the Chevy in France.
 
#4 · (Edited)
You are correct, kbuhagiar, I am indeed in France, and while it is not a legal requirement for me to modify the tail lights of my car (due to its age), I would really like to make that change for safety reasons: the last cars sold in France with red turn signals date back to the early '60s, basically no one here has seen that set-up, and I am always scared of being rear-ended, with those red turn signals or just 1 brake light when the other one is flashing!
Your post did make me think of the 1980s Oldsmobile Delta 88 (the full size sedan), which had amber turn signals, separated from the brake lights.
Separating the tail lights and the bulbs is the easy part. The additional wire from the brake switch is easy.
 
#5 ·
Clip the wire from the Bk lite sw that goes to the turn switch (white wire) then run that to the brake light bulbs
leaving the other wiring intact will run the turns and tails

To get turn signal dash indicators, splice the wire for the FRONT turn signals and use that for the dash indicator. The front turns do not need to be turned off to display brake light signal see?
 
#8 · (Edited)
Clip the wire from the Bk lite sw that goes to the turn switch (white wire) then run that to the brake light bulbs
leaving the other wiring intact will run the turns and tails

To get turn signal dash indicators, splice the wire for the FRONT turn signals and use that for the dash indicator. The front turns do not need to be turned off to display brake light signal see?
Thank you, Latech, I was typing the same thing as you, while you were typing it yourself!

And yes, I need a new brake wire and separate bulbs, but that was the easy part. Finding where to connect my new brake wire was the confusing part (considering how the different circuits seem to be integrated), even if I knew it could not be that difficult!
 
#6 ·
'49 ford coupe, your diagram shows pretty much what I have in my car, even with the correct colors. Your diagram is bigger and clearer than the one in my shop manual, and it does help.
So it seems the orange wire brings always hot to the brake switch, and then the white wire is the brake light signal. If I get this right, I just need to connect the white wire directly to the brake light, I am set for the brake lights, right?
As for the signal lights, I do not have anything to do, as the "turn signal/hazard switch assembly" will work as it did, except that it will not receive the brake signal anymore.
Did I get all this right?
 
#9 ·
not sure if it meets your requirements, but the easy way would be to come off the brake switch with new brake lights direct to the back end. your emergency flashers will need to stay with the turn signals, but you would have brake lights too. not sure if you'd need to add any diode to keep feedback from lighting up brakes when flashers are on or visa versa (did i just use french there???) should be easy enough to rewire a light or 2 back there 😂

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#10 ·
I did this on my 1959 F100.
The trick is to run a new brake light circuit to the rear and get into your turn signal hub in the steering column and disconnect the circuit that comes out to power the brake lights.
I thought it was way more complicated as I asked a guy to quote me to do it, he told me it would take him a weekend with the vehicle left at his shop and $400.
The $400 quote told me that I should look at first myself.
It was pretty easy and took a couple of hours for me an amatuer...

PS: I had a towing hitch and lights with that so I converted my trailker to amber as well to keep it simple...
 
#11 ·
When wiring my '40 Ford pickup, and noticing that the new kit wiring had only two wire for my rear stoplights, I got concerned. However, I was using a GM column from a donor car, and the kit was made for plugging the kit insert into the GM column. The GM column is a brilliant system that, among other attributes, internally separates the directionals from the stop lights, using two wires. Everything is done within the GM setup! What a marvelous piece of engineering it is.
It is also possible to use the options on the signals to run other features, but most rodders expect it will emit 12 volt signals, and get frustrated with them. The options are based on relays that use the closed circuit to trigger the particular relay to send 12volts then. Most rodders don't know how to wire an auto relay to work on 12 volt signal, or a ground signal. This makes the GM signal switch a versatile tool. A last feature is that the column will not allow starting the engine to be started unless the transmission is in Neutral or Park.
It's just a matter of plug and play!
 
#12 ·
When wiring my '40 Ford pickup, and noticing that the new kit wiring had only two wire for my rear stoplights, I got concerned. However, I was using a GM column from a donor car, and the kit was made for plugging the kit insert into the GM column. The GM column is a brilliant system that, among other attributes, internally separates the directionals from the stop lights, using two wires. Everything is done within the GM setup! What a marvelous piece of engineering it is.
Pretty much every vehicle is wired that way since the 50s.
Combined stop/turn is normal for the US
The OP is hotrodding in France,
 
#13 ·
Too bad it's more difficult overseas. It's not that easy here, but it's always impressed me how much the American hot rodder has impressed overseas followers.

Thanks for the follow-up.

If anyone's interested I could perhaps find my schematics of both ways of wiring car relays. Really didn't know that before I needed to.

Elder Rodder