1936 coupe

i have a 36 coupe and i am doing a painless wiring harness. The problem i am having is the tailights. i have three wire and a dual filament bulb, what can i do to hook up the blinker,brake,and parking to the dual filament bulb. any help would be greatly appreciated. and on top of all this what resistance do i have to use if i want to add leds, when i put them in and hit the blinker they just stay on as if the bulb was out.

The blinker stays on because it thinks the bulb is out.
The LEDs might consume 0.5W compared to a 21W bulb.

There should be a circuit to switch the flasher to the stop lights - it usually involves a DPDT (or 3PDT) relay per side.
(In a similar fashion, we used to have combined flasher/reverse lights, but now reverse lights are separate.)   
I'm sure someone else will have a link if it isn't on this site....

i see the dpdt relay if i am not mistakend it is round. and there is one per side and it does flash. but i would imagin it would be on one circuit . which would mean one wire. but in this case i have two. is there anyway i can use a nspdt relay to interupt the brake light when the flasher comes on???

hi,

is the turn signal switch on the column (built in?)...GM column?  or is it separate under the dash?

m

Ok so i thought I posted this yesterday but I guess not. The switch is on the column and the column is out of a 1976 grand prix if I am not mistaken. I found something online that might help but very confusing, I was wondering if somebody can help wtg drawing up a diagram. I am on my iPhone now I will be posting it within the hour. I really hope somebody can help me thx in advanc.

Can somebody PLEASE make sense of this thx!

Here is one way to solve your dilemma:

1. Make sure you have a turn signal switch that has a brake light input. Universal turn signal switches, like the ones made by Signal-Stat, come in two flavors, one is for separate brake and turn lamps (like heavy trucks and foreign cars) and the other combines the brake and turn signals into one lamp (like a typical American car), this is the one you want.

2. On your brake light switch there are two wires, one is the power wire and the other goes to the brake lamps. Using a test lamp, determine which wire goes to the brake lamps and disconnect it. Cut the terminal off of it and splice a wire to it long enough to reach the turn signal switch (14 gauge for 6v, or 16 gauge for 12v). This wire will become the right rear turn/stop.

3. On the brake light switch, connect a 14 gauge wire to the now unused terminal and run it with the other wire to the vicinity of the turn signal switch. This is the brake wire that will be connected to the turn signal switch.

4. Run a wire from the turn signal switch to the left rear light. Cut the factory brake light wire at the left rear. Connect the new wire to the lamp wire you just cut. The harness end of the cut wire should be folded back and taped up.

5. Convert the sockets in the front park lights so they will accept dual filament bulbs like the brake/tail lamps. Connect the existing park lamp wires to the dim filament of the park/turn lights. Run two wires out from the turn signal switch; one to each of the front turn lamp bright filaments.

6. Now you should have five wires under the dash: RF, LF, LR, RR, and Stop. Connect these to the turn signal switch per the manufacturers instructions.

7. The turn signal switch will have one or two wires still unconnected. One will run to the L terminal of the flasher. The other wire if present is for the turn signal indicator in the switch; If you have a 3-prong flasher, this wire will connect to the "P" (pilot) terminal. If you have a 2-prong flasher, this wire will be left unconnected.

8. Connect the X terminal of the flasher through an inline fuse to the ignition switch or the accessory power panel on your firewall. If the turn signal switch has a hazard function, this should be full time power. If not, it should be wired to key-on power.

IMO this is the simplest way to do it right...assuming your harness is in good shape.

If you can find a good original Chevrolet accessory turn signal switch, you will get the added benefit of having the turn signals self-cancel. They have a wheel in them that rolls against the back of the steering wheel hub connected to a mechanism than makes them cancel just like a more modern car. They also have a fused power lead that will screw directly into your accessory power panel.

Hope this makes sense...

ok guys so i figured everything out. i ended up relay isolating the brake and it worked perfect. now my problem is the leds. is there anyway to trick the car into thinking that they are not out???Maybe a high level of resistance...i dunno hope u can help

IMO the best is 2 normal bulbs, or a single bigger bulb (eg - 40-50W).
Paint it/them flameproof black if needed.

Otherwise you need 50W of resistance - eg, 4 Ohm 50W; or 2 x 10 Ohm 20W etc.

Or get LED suitable stuff.

The simplest way is to buy a flasher (#AM-02R) Electronic Flasher for LED’sdesigned for LED's or put a dummy load (#L52DL2) (Sold only in Pairs) in line. Watsons is 1 suplier but thier are plenty https://www.watsons-streetworks.com/leds_taillights.html this is a link to the page that has these 2 parts. hope it helps.