I have a '94 Acccord and I was going to do a retro with S2000 projectors but i also wanted to do a side project while the headlights were off the car.
I wanted to put white LEDs into the highbeam and the lower turn signal lights in the bumper..hook them up to the parking lights so they go on with the parking lights.
Then have them turn off when my low beams when on.
I dont want to use a switch because im lazy.
Its possible using relays right? I just dont really understand how.

Thankss

 

It may be possible by using 2 30A relays with 5 terminals each. You can have one relay normally open on the positive wire of the parking lights that completes the positive circuit of the LED's, and then another relay normally closed on the positive wire of the low beams, which will cut the ground to the LED's when you turn on the low beams.

I think that would work but I'm not 100% sure. You'll have to do some reading on relay wiring. Look up Bosch 30-amp SPDT (single pole double throw) relays.

 

- ive tried to look up relays and try to understand but i just dont get it.. lol. ill see what i can find. i got more free time lately..
- if anyone else knows for sure and can possibly draw a diagram, please hit me up here.

thankss

 

You think you can possibly do a diagram of it so I can understand it fully and I'll do a test when I get the relays tomorrow.

 

http://www.the12volt.com/relays/relays.asp

 

I don't have any Accord wiring diagrams so I don't know of any wire colors or locations. I could draw up a more "generic" diagram showing how the different parts would be connected, but it wouldn't be vehicle-specific. You'd have to look up the wire colors and locations in a manual yourself.

 

I think this will work. Black lines are ground wires. Red wires are existing power wires. Blue lines are new power wires, and green lines are the new positive output for the city lights.

As you can see, the power for the city lights comes off the parking light power wire (LED's should be fine getting power from the parking light wire), and when the parking lights are turned on, power is applied to the relay with the normally open connection, thus connecting the power wire to the city lights.

The ground for the city lights is connected to the normally closed terminal of the other relay. When the low beams come on, power is applied to this relay and will open the ground wire connection, causing the city lights to turn off.

 

A single DPDT relay could probably do this, but those are much less common that the standard Bosch-type SPDT relay.

 

Alright. I'll test it out tomorrow. Hopefully. I got class soon so I'll try to understand it and match it to my car too. I'll let you guys know.

The 12volt relay website. I've seen it a million times but it is probably one of the worst explanation I have ever seen.

 

its been almost two month and i barely got a chance to do this..

it didn't work =/ .. at 1st 1 out of the 4 LEDs barely turned on. and then nothing.

i checked the ground and nothing. all the other connections are good too. o.O

any ideas?

 

What is the forward voltage and current of the LEDs being used? Did you correctly calculate the required resistor size and install one?

Use a multimeter, and verify that you have voltage out of the relay when expected. You can usually hear them click when they transition as well.

If all else fails, test each LED individually with the correct resistor inline directly off the battery.

 

Are you sure you hooked up everything according to my diagram? If I had the time and money I'd test out something like that myself, but I just don't (especially the money part).

 

yea, from patrick's diagram, it should work, if connections arent the problem, then maybe it could be the led's? ive had my share of led's and have had quite a few duds, what type are you using?

 

Sorry I haven't updated. But I'm thinking the heat from the s2ks probably fried them. I tried hooking them up straight to the battery and nothing. I was
using some basic varad LEDs. I had done something similar but it was in the lower bumper lights that don't get much heat. I didn't think about it this time. Oh well.
I'm planning to buy a drl kit instead and do that.
Thanks tho. The diagram with still help with other stuff.

 

UPDATE: I used your wiring diagram for the lower bumper lights on my Accord.

- I took some 3496 (i believe) brake lights and put them inside.
- Wired the second filament (brighter one) to the regular turn signals. (Doesn't affect anything here with your wiring.
- So now i have the basic + and - from the bulb. The first filament which is the dimmer one i hooked up as you said before and the negative as well.
- Redid the wiring as you told me

Conclusion: The lights light up with parking lights and the turn signals work fine.
Problem: The lights wont turn off when the low beams go on.
I tried hooking up the particular wire that is suppose to be attached to the low beam to the car battery and they dont turn off.

Any ideas?

 

Waiting on answer! =P

I'd just leave them on all the time but in Cali we aren't allowed to have more than two sets of lights on.

Low Beam + Fog in my case.

 

In the beginning, I just assumed that you wanted to have city lights in your highbeams, and this diagram works perfect for it, but I see now that you want the same effect with your bumper lights. From what I see, having a dual filament bulb makes things a little more complicated. Because both the filaments share the same ground, and the way the relays work, this would mean that you won't have your bumper turn signals at all when your lowbeams are on. I think that wiring the bumper lights gets it a little more complicated, I apologize but I wouldn't be able to help you out on this one

 

Well, lets ignore the whole dual filament thing.

I understand what your saying but...
Didn't you notice, you said that the relays should cut off power to the ground and nothing should work once i turn on my low beams.

How come the lights still stay on and my turn signals work?
According to the diagram and what you said. It doesn't really matter that its a dual filament.
It should still turn off.
The reason i'm still asking is because i'm still interested in this.
I'm pretty sure TONS of people are interested in something like this..

Thankss..

 

I understand, and I DID notice, I was just typing so much that I forgot to add that in, but they obviously still work with the lowbeams on, so that must mean that the second relay which cuts off your ground must not be working or is not wired correctly. I would start with that to begin diagnosing your problem.