This is a Series circuit..

The sum of Voltage drops across each light bulb is equal to the total applied voltage, the Amperage (current)is constant..So the more bulbs you add in Series, the dimmer each bulb will become.



Ina Parallel Circuit, the voltage is constant at each light bulb, but current (amperage) is divided across the indivual bulbs.. So the total current is the sum of each lamp's current draw..Adding more bulbs in parallel, will not increase or decrease brightness of the bulbs, they will remain at a constant brightness...But currentwill increase proportionately per each extra bulb added...So heavier wiring is needed.




This follows the simple OHMS LAW equation

E=I x R
E (volt) = I (current or AMPS) x R (Resistance in Ohms of each bulb)

So lets substitute will reall numbers, shall we?..

12V = 2 amps x 6 ohms..per bulb,
Now add another bulb in series, your total resistance has doubled.

Now it will be; 24V = 2 amps x 12 ohms..But since we only have a constant 12 volt system, the voltage at each bulb in this case will be only6 volts in this two bulb series example because the current flowing through each bulb was cut in half, the other 6 volts is being used by the other bulb..Proven; 12 volts / 12 ohms = 1 amp..Add yet another bulb in series at the constant 12V suppied..the voltage across each bulb will drop by 1/3, or 4 volts per bulb...and so on...Simple.

 

I overreacted....It was a fuse. Thanks for the replies. Fixed the headlight and wired the marker lights correctly. All is well.
Thanks again & Happy New Year!

 

Dennis you totally crack me up!! Love the examples

 

Dennis, thats all good info, but with the BCM controlling the headlights there is no way to go in and wire everything in parallel. Plus the facory wiring size wasn't meant for this and is not a thick enough guage to run, in this case, 10 or more marker lights.

 

Preceisly!

 

oh, ok....phew I passed car electronics 101

BTW...the school you got this pic. from is about 20 minutes from my house.

 

priceless!!!

 

Mr Dennis..I have a question!!

I just installed my off road lights. In each light is a 5w ambermarker light. But thats really bright. A little too bright to be driving all the time with. How do I make them dimmer? The wiring harness is pre-made..should I take it apart and put them in a series circuit?? Or should I go find a dimmer bulb?

Also, for the time being, I couldn't find a readily available power line to a parking light so I pulled the LF Parking fuse, stuck the wire in there and put the fuse back. Is this safe? If so, which side of the fuse is on the safe side of the fuse so that if my super bright markers short out, they blow the fuse?

 

I'm not Dennis but I can help ya. First off don't just tick the wire into the fuse socket and stick the fuse back in to hold it in place...in time you will melt the fuseblck as it's nothing more than plastic. They make crimp on connectors that do the same thing you are doing but it's much safer and much cleaner. As far as dimming the bulb the easiest would be to just buy a lower wattage bulb, may cost a few bucks each. As far as which side of the fuse is the fused side that you want your power on, my advise to you would be to just hook up the power to the constant power side of the fuse and run an inline fuse on the power wire going to the lights. If you run the lights on the fused end of the fuse then you risk exceeding the amperage of that fuse.

 

yeah..I would've said something like that....