Maker Pro
Maker Pro

Amateur Help

abeberness

Feb 18, 2013
3
Joined
Feb 18, 2013
Messages
3
I'm trying to figure out how to make a simple circuit for my car. I have a very basic understanding of electronics and I thought I had this figured out, but the more research I did into it, I realized that it wouldn't work. Basically, I'm getting new headlight units that have Daytime running lights built in, but my vehicle doesn't have that capability. So, here's the basic outline of what I'm trying to do. I have two power inputs that the circuit needs to determine if the daytime lights will run, one from my accessory port on my stereo and the other from my regular headlights when they are manually switched on. I thought I would use two transistors as switches to do it, but it doesn't look like it will work. Basically if there is power from the accessory cable, but not from the headlights, then the daytime running lights will be on, but if there is power from the accessory cable AND the headlights, then the daytime running lights turn off. The reason I am using the accessory cable is so that the daytime running lights aren't on when the car isn't on. If I could get a better understanding of what to use and how, maybe with schematics would be even better, I can read and understand those for the most part, that would really help me out.

Thanks in advance!
 

john monks

Mar 9, 2012
685
Joined
Mar 9, 2012
Messages
685
What kind of lights do you intend to use? LEDs? Incandescent?
Do you intend to run separate wires for these lights?
Are they going to be mounted in the same housing as your regular headlights?
 

abeberness

Feb 18, 2013
3
Joined
Feb 18, 2013
Messages
3
Yeah these daytime running lights are built into the new headlights I am getting. They have the main headlights and next to those, they have these simple incandescent lights. I was going to run their own wires from the battery into this circuit to power them.
 

john monks

Mar 9, 2012
685
Joined
Mar 9, 2012
Messages
685
I assume that you want the Running lights to be on whenever the car is running.
So it seems to me what you need to do is find something that is getting power when the car is running and run a wire. I don't know what kind of car you are driving and therefore not familiar with the wiring. Maybe you can run a wire from your stereo or radio. I assume the running lights only draw a few amperes. Are the lights small? Do you have any identifying numbers on your lights so I can look them up?
 

CocaCola

Apr 7, 2012
3,635
Joined
Apr 7, 2012
Messages
3,635
I assume that you want the Running lights to be on whenever the car is running.
So it seems to me what you need to do is find something that is getting power when the car is running and run a wire. I don't know what kind of car you are driving and therefore not familiar with the wiring. Maybe you can run a wire from your stereo or radio. I assume the running lights only draw a few amperes. Are the lights small? Do you have any identifying numbers on your lights so I can look them up?

Vehicle lights are almost always on relays, so that switching current is minimal at that dash switch location and one control line can control multiple items without issues...

Even small running lights can draw 10-15A in a automobile, not something you really want to piggyback on the radio circuit...
 

abeberness

Feb 18, 2013
3
Joined
Feb 18, 2013
Messages
3
Vehicle lights are almost always on relays, so that switching current is minimal at that dash switch location and one control line can control multiple items without issues...

Even small running lights can draw 10-15A in a automobile, not something you really want to piggyback on the radio circuit...

I know I don't want to piggy back it off the radio circuit. I was just going to use the radio circuit as a basis for when the car is running. That's why I thought the transistor would be the best idea. That small current running from the the radio would open the full current to the lights. I'm driving an 04 dodge neon.
 

CocaCola

Apr 7, 2012
3,635
Joined
Apr 7, 2012
Messages
3,635
Skip the transistor or other solid state method, and just use a mechanical really, it's simple and very effective (the norm) for automotive use, you can get them at any auto parts store for a few bucks...
 
Top