Newbie here needing help

Thread Starter

golfersphen

Joined Jan 9, 2011
17
Hello,

My name is Oscar, and I am new to the Forum. To begin with, I have ZERO experience in building circuits and dont know anything about the terminology used here. So I beg forgiveness.

I hope you fine people will be able to point me in the right direction or maybe even design one for me so i can do the building myself (which i would enjoy doing even though I may drown the first few tries. haha)

Here is what I am wanting, for my Jeep. I would like to spice into the wire(s) going to my dome light. This spice would lead to a new circuit/button. I will talk only about the button right now. This button would be located on my dash and would be a momentary on switch. When pressed, it would turn the dome light on for X number of seconds/minutes. Ideally I would like the time to be programmable. I am thinking that for sake of ease (how easy, i really dont know, but my odd logic tells me it would be easy) that i would just limit the time to minutes instead of both minutes and seconds or just seconds.

Now, the light is on for a set time limit. Now with the push of the button a 2nd time, the lights will then turn off and the timer will reset to wait for the button to be pressed again to start the time and turn the light on.

As for the circuit, I have no idea on how to even begin to make something like this.

As for slicing into the the wire's leading to the dome light, I would still like to have the factory controls work for few different reason, hence the splice. So with that in mind, would there need to be something there to prevent the current from back flowing into the other circuit?

Now I really hope my asking for help in this mater is not out of line. I think it would be great if someone could design this for me in such a way that even I could understand it, so I could go out and buy the parts and build it myself.

Lastly, how hard would it be to make the like so it Fades off instead of an instant off?

Anyways, thank you all.

Oscar
 

Wendy

Joined Mar 24, 2008
23,415
You would be better off making a light similar to one of the dome LED types.

Automotive circuits are tricky around here.

Automotive Guidelines

You would need to go under the dash and add an extra piece of wire, while 3 AA batteries would last for months.

This could be done. The fading adds complexity, but it could be made fairly easily.

When the the mods review this thread I'll draw something up. How long do you want the fade to last.

I would recommend going through volume 6 in the ebook on top of this page.
 

Wendy

Joined Mar 24, 2008
23,415
If you want to light up the dome light and leave the computer connection to the dome light intact you are going to have plan for that. I notice you mentioned that, so you are aware of the issue. I'll come up with something simple, but it won't be that simple. How about a timer with a knob that you can set the time for? I'll need a max and minimum time for the light if this is acceptable.
 

Thread Starter

golfersphen

Joined Jan 9, 2011
17
ok, i responded but i dont know what happened to it.

as for the stick-it LED light... i have thought about that, but that is too easy. Too Easy is no fun! haha

As for violating the automotive guidelines. If at any point, if it seems like I am violating the guidelines, then let me know. I do not want to get anyone in trouble. Forums like this are few and far between. As a result, we want to do anything possible to keep them going.

For the Fade out of the light, just scratch that. I dont need it.

I have already traced the dome light wire(s) that comes out of the instrument panel to the light, and have spliced into it and placed a small switch. so removing the switch and connecting to this new controller would be easy.

As as to why, well one, it sounds like a fun challenge since I know nothing about it. The motivation behind the desire to meet this challenge is the way jeep has their warning chimes and door sensors hooked up. The warning chimes (example, leaving the head lights on) only sounds if the door sensors are hooked up and working. And since it is a wrangler, i go summers with no doors and topless. Now I could either drive around with the dome light on all the time, or put in the cut off switch on the line to the dome light, or pull the fuse. However pulling the fuse disables the chime, and driving with the dome lights on just is not good. And letting it sit with the dome light on is bad. The cut off switch is a good solution, and turning on the light when needed is easy, but no fun. So I am wanting to give myself a challenge to help keep me out of the bad kind of trouble, verses the good kind of trouble which is what this challenge is. haha. Make any sense?

Oscar
 

Thread Starter

golfersphen

Joined Jan 9, 2011
17
before i added the switch inline with the power wire going to the lights, i would either pull the light bulbs out and were placed in the glove box, or just disable the door switch. the problem is disabling the door switch or pulling the fuse disables all of the warning chimes.

The only lights I have in the cab of the wrangler are located in the speaker bar that is attached to the roll bar above the head of the front two seats. Its these lights that I recent spliced into the feed wire of, and placed a small toggle switch.
 

Wendy

Joined Mar 24, 2008
23,415
I've run out of time to draw schematics (you are on my list, but it is a list). Between a full time job and other stuff I've run out of time this morning. Basically it will be a variation of the LED special effects in my LEDs, 555s, Flashers, and Light Chasers Chapter 12.

You mention light bulbs, are you wanting to keep the existing bulb? My current assumption is probably yes.

What did you think of the knob for the time setting? I asked for a minimum and maximum time. If you don't want an adjustment just let me know how long you want the light to stay on.
 

Thread Starter

golfersphen

Joined Jan 9, 2011
17
I have been looking for good LED blubs to place in the two dome light enclosers, but so far, I have not found anything special. I am waiting to hear reviews on this on: http://www.roundeyes.com/Jeep_LED_Interior_Light-Jeep_Interior_LED_Lighting_Kit_4.html

I am also going to be wanting to add a few more lights to the same circuit under the dash by the feet area, and in the back storage area.

as for the timer, I am thinking just a simple 2 minutes would be fine. I am not a big fan of the knob idea. Dip Switches would be ok however. Since this will be in a jeep, it will get bumped around a lot, i would prefer no knobs or dials.

no hurry. I understand. i am just extremely grateful for the help.
 

thatoneguy

Joined Feb 19, 2009
6,359
When looking at LEDs, don't concentrate so much as the pure mcd brigthness level as the angle. Some very narrow beam LEDs are tiny flashlights, bright, but useless for area lighting.

White LEDs essentially have the focusing lens as part of the unit, so you will want to get the widest angle you can find. You'll still end up getting several, for example, to go in a strip along the front and rear of the roll bar. For that layout, I'd suggest SMD LEDs, they are a bit harder to solder if you haven't worked with them much, but with the right "dressing", they would be nearly invisible until turned on, at which point you could find anything you dropped in the jeep.

There are pre-made LED strips for lighting, but a DIY hobby thing for over the winter is understandable too. For controlling them/current limiting the string, get a "BuckPuck", and tie the dimming line to the "dim" line that goes to the stereo, All lights can then be controlled by your dashboard light intensity knob/switch.
 

Wendy

Joined Mar 24, 2008
23,415
One more question. Is one side of the socket ground? I'm assuming ground is the negative side of the battery. It sure would make things simpler if it were.

Another way to fight the narrow angle of LEDs (as thatoneguy mentioned it is a serious problem) is many leds, all facing different directions. If you have a white plastic dome over the bulbs it should disperse rather nicely. Some experimentation will probably be in order.

A quick tutorial on LEDs in general can be found in chapters 1 and 2 of an article I wrote a while back, LEDs, 555s, Flashers, and Light Chasers. A general rule of thumb is LEDs must have a resistor or something that does the same job, always. If you connect one to a 12V car battery without it you will see the toxic magic smoke escape, not a good thing.

The timer and dip switch controller is easy enough. The fade is pretty easy, but will probably require some experimentation on your part to get it the way you want.
 

Thread Starter

golfersphen

Joined Jan 9, 2011
17
ok, sounds as if i am getting more and more homework from all of you. haha

I am going to have to research these different kinds of LEDs and decide what I want to do.

;-)
 

thatoneguy

Joined Feb 19, 2009
6,359
do buckpucks contain the resister that is needed?
Sort of.

They are a current regulator, and control dimming by PWM (Pulse Width Modulation), which is a fancy way of saying turning the LEDs off and on really fast (thousands of times per second). The shorter the "off" period, the brighter the LEDs are.

The problem arises when you have the multiple strings of LEDS. BuckPucks can supply various currents, but you still only have a max of 12V to work with (engine not running). This means 3 white LEDs per "string". From there, you will need to add some resistors to even out strings, or use one of Bill Mardsen's circuits to expand the BuckPuck output a bit.

BuckPucks are made to drive a single LED, or a single string, regulating the current, eliminating resistors When you are adding more than one string, or LEDs that don't draw heavy current, it gets more interesting, especially when you want to dim them. The best dimming method (PWM) is already provided by a buckpuck from luxeon. Now it's just a matter of deciding which/how many LEDs you want to get better calculations of what you should get as far as parts.
 

Wendy

Joined Mar 24, 2008
23,415
OK, this took longer than usual. We'll see if it is in time to be of any use for the OP. I basically took my best guess on the white LEDs. To reduce the parts count I used only two LEDs in the chain, the current would vary too much otherwise.



The timing resistors are very approximate, and I used a CMOS 555. A Radio Shack TLC555 (not the LM555) is a good replacement.
 

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Thread Starter

golfersphen

Joined Jan 9, 2011
17
Bill,

I want to thank you for the diagram. Now i need to print it up, and do homework on the symbols and such. this is going to be fun ;-)

Another question if you dont mind, what program did you use to create the diagram?

I really like this site and all of you for your input. Thank you again

Darin
 

Wendy

Joined Mar 24, 2008
23,415
Another question if you dont mind, what program did you use to create the diagram?
This is where it gets funny. I made a set of templates you can freely download from here to draw with. The actual diagrams mostly come out of my head, I do not use spice programs.

At the point the person asking for my package goes away and hopes I don't follow. :D

Bill's Index

I am very active on this site and do not sharing the knowledge. It is also why got my user status, I do some writing on the side.

Do not be afraid to ask questions you might think as dumb. We get a lot of beginners here, and have no problems helping them.
 

Thread Starter

golfersphen

Joined Jan 9, 2011
17
Bill,

again, i thank you. I currently have a parts list I want to ask you to look at to ensure i am decoding the diagram correctly. I also have a few questions on the diagram, but of course, i left all my note at work.

Again, i thank you and will be getting back to you with my questions if you dont mind!

Darin
 
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