Hi everyone,
I plan to convert my old light bulbs on my 77 Corvette to newer LED aftermarket lights. I want to ask if there is the need to add resistors in between my new LED lights and the wires going to each signal. Since the draw for the LED lights are less than the light bulb I am afraid that if I make straight connections, I will either burn or cause hyperflash to the new LED lights.

Also can someone tell me which color wires on a 1977 Corvette go to each signal? (color for: left and right signal, color for: ground, color for: taillight, color for: brake, color for: back up)

 

The only thing I know from my motorcycle experience is that you'll need a solid state flasher. The LED's don't draw enough juice for the old style flasher.

 

Contact Papawana for a schematic.

 

I don't think they would flash very quickly, I think they wouldn't flash at all. The stock incandescent bulbs heat up a bi metal strip in the flasher that opens the circuit til it cools and closes the circuit. The LEDs dont have enough resistance, to heat up the flasher, as you already know, so the lights just stay on. The simplest solution is to just install the LED flasher as lowbuck72 said. Simple plug in instead of soldering in resistors.

 

I want to go back to the regular bulbs. A previous owner put led tail lights in on my 71, not only are they not as bright but they annul the fiber optic monitoring which I think is very cool….

 

Don't use resistors, it defeats half of the purpose of LEDs. Not only do they put out more lumens, they use a LOT less current. You need a 3-wire LED flasher (two, actually, and likely swap-able bases). If you do the side marker lights (the ones that flash with the turn signals), you will need either bi-directional LEDs, or BlinkerGenies.

Here's everything I learned while replacing every single bulb with an LED in my 80. There should be a link to wiring diagrams in there. And, no, my DRLs don't look green, it's the camera, but they do shine through the 80s yellow tinted lenses. I think the 77 lenses are clear.

https://www.corvetteforum.com/forums...s-learned.html

 

Ah I see. I plan to ONLY put LED's for my tailights. (How many 3-wire LED Flashers do I need just for the rear 4 tailights?) I want to keep everything else (side marker lights, front marker/directionals bulbs, front side marker lights) stock with the bullbs. Also do I only put these LED Flasher's in between the directional signal switch wires? (Not the: stop brake light, reverse light, headlight illuminating light?)

 

If the LEDs don't have enough resistance shouldn't that mean I need to put resistors instead of LED Flashers? Or do I need to install both. I am only altering my rear tailights to LED ones.

 

I think he meant to say "LEDs don't draw enough current...".

This is the LED flasher I use in my 79 and my 80. I needed the reversing base in the turn signal position, YMMV. There may be other solutions for earlier cars.

It should handle any amount of LEDs, from all of them, down to zero (all incandescents). Don't add resistors, you will end up drawing the same current as stock, meaning no gain on LEDs other than more lumens.

 

Gotcha, so do I install the electronic flasher in place of the thermal flasher in my 77 (which I think is at the bottom right passenger side of the car)? Basically take the thermal one out and straight swap it for the electronic one, and swap two of them for both sides? And then once that is done I just straight up splice my new led lights into the wiring of the 77 rear tailights?

 

The flasher(s) don't go in the fuse block in 77? They do in 79, and you need two, one for indicators, one for hazards. Do you have a hazard flasher in the fuse block? I s'pose the important consideration is that the base is the same (two spades at a right angle, unless that is different in your car), and it is specifically an LED flasher, which I think means an independent ground (third wire).

What are you splicing? LED taillights should be a direct bulb swap. Though you can use a pair of 1157s on each side (4 total) if you replace the inner bulb sockets, and run each side's sockets in parallel, as I have done. Are you putting in something like the round LED taillight assemblies you can see a truck stop? I'd suggest using a waterproof connector, so the bumper can be removed without cutting wires.

 

From my research, on the 77' 1 is in the fuse box and 1 clips on behind the passenger side dash. (Passenger side dash is the directional one and the one for the hazards is the fuse box one)

No so the LED tailights I am installing are not LED bulbs, they are strips kind of like truck LED lights that fit into the hole of the 77'. They have wires coming out of them and each wire goes to each function. (Brake, directionals, reverse, ground, illuminating). Here are some pictures of my new tailights I want to install.

 

So now that you can see the lights I am installing, apart from the function for the directionals (which I will be using electronic flashers for), do you still think I wouldn't need resistors for the tailight's other functions (brake, constant headlight, reverese)? I am afraid I will burn some of the LEDs if I just plug and play the wires to each function. Will that not happen? Or are there fuses that go to each function which would blow first?

Also how do I swap the hazard flasher for an electronic one (my hazard flasher goes into the fuse block). Do they make specific electronic flashers that can be swapped into the 77 Corvette fuse box and fit all the same? Or is it just a normal flasher that theymake electronic ones for now and can just be swapped out? For example the directional thermal flasher underneath the passenger side panel of my 77' only has 2 prongs. My electronic flasher that I will be replacing to work with my new tailights has 3 prongs. I'd imagine the old one did not have a ground prong but my new 3 prong one does. If that's the case then I can simply ground it but if it that isn't the case, how do I go about installing the 3 prong electronic flasher that replaces the 2 prong thermal one.

Sorry for all the questions, I am in the process of learning everything and don't want to ruin anything.

 

If it goes in the fuse panel, the LED flasher I linked above should fit.

Are these LEDs rated for vehicles and 12V (nominal)?

If so, it doesn't matter if it is the brake lights, reverse lights, or turn signals. The LEDs will see 12V (up to 14.5V or so, with the alternator charging), and will light up. Some individual LEDs require a current limiter, but LED bulbs or assemblies made for cars do not require that. They won't "blow" if they are made for vehicles.

Please post a link!

 

Yes they are made for vehicles and are 12V. So all I need to do is install the electronic flasher relay for the turn signals and I should be ok. Everything else should just be plug and play with a waterproof harness for each tailight.

 

You'll also need to replace the LED flasher for the hazards, if you want that circuit to work.

As for wiring, can you post a link? Will they be all 4 the same, and are they 4-wire, with dim and bright red rings, and white centers? Or is something else going on?

 

Yes I can: It doesn't say much on the ebay site because they aftermarket to fit into a Lotus Elite but there are 5 wires (ground=white, reverse+black, stop+red, tailight+brown, turn+green)

https://www.ebay.com/itm/324838486728

 

They are 5 wires because the turn signal and stop light are on different rings of the tailight. So do you know how I should go about wiring them into the one wire that was for both stop and turn on the original set up of the car?

 

Thanks for the link! It will be interesting to see how you connect these. C3s do not separate the brake lights from the turn signals, at least not at the rear of the car. But as long as the stop lights come on strong, that should be sufficient (that is what we have now, of course). To get the amber to work, you'd need to send the signal back from under the dash.

You can see that the turn signal circuit is amber, in the video on their Facebook site (link at eBay, but blocked by the Forum), but I didn't see the brake or reverse light demonstration.

Please post a video when you get these running! You could also test the 4 light circuits with a battery, and see how you want to wire them.

 

So in order to get the amber light to work could explain how I should wire it? How do I seperate the turn signal wire from the stop wire on the C3. The turn signal amber wire is the yellow one, where do I connect it to and how do incorporate it with the electronic flasher with out it being the same as the stop light function?