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Discussion Starter #1
i am wiring up a set of 12vDC LED rock lights.

I wired them in parallel and one of the lights failed. it was previously working. i didn't change the wiring to it, just to the other light on the same side.

I am wondering if wiring in parallel can draw too much current somehow...the alternative hypothesis is that it spontaneously failed while i was wiring the other light.

when i hook up a multimeter to it, i get zero resistance through it.
 

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i am wiring up a set of 12vDC LED rock lights.
when i hook up a multimeter to it, i get zero resistance through it.
Reverse the meter leads and see if you get the same resistance reading (using the Ohms function on the meter). I believe that the "D" part of LED stands for diode, and diodes only conduct DC in one direction. (You may have connected the changed one backwards.)

Good luck
 

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<0.5 ohms in both directions? Sounds like it's shorted.
 

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Agreed, LEDs only work in one direction but hooking it up backwards wont ruin the led. Turn your multimeter to diode , and make sure the red lead is in the ohms position. it should say ol or open now. connect the black lead from the dmm to the cathode end or shorter end of the led and the red end to the anode or longer, usually angle cut end. You should get a reading of around 1600mv, if its alot less then the led shorted internally if it says open or ol then its busted.
However if it passes then check your wiring :thumbup
 

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Discussion Starter #6
yeah, i think its shorted too. it worked fine earlier this afternoon. all i did was wire a second one up in parallel to it.
 

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i just wired up a couple lights on my bumper. i used a 30 amp relay and 12 gauge wire. wired in parallel. the switched lead to the lights splits and runs to either light. then they are grounded separately to the frame using a bolt that holds the bumper on.

at one point one of them wasnt working, bad ground connection. and then at another point, neither worked, bad hot lead off the battery. make sure you check your ground and positive. i wouldnt assume the lights bad. double check your connections before you say the lights bad

oh and if you run them is series you wont see top performance out of your lights because there will be twice the resistance that you'd have in a parallel setup.
 

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Wiring them in parallel is the correct way. I would assume that its either a bad connection somewhere or your light decided it was its time to go.
 

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thats one of the issues with LED lights. They work great and the low draw is a plus but when they decide its time to go they are dead.
 

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Discussion Starter #11
kind of expensive unfortunate event.
the light only had like 2 minutes of burn time on it. i hope the other 3 hold up longer.
 

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Discussion Starter #12
i just wired up a couple lights on my bumper. i used a 30 amp relay and 12 gauge wire. wired in parallel. the switched lead to the lights splits and runs to either light. then they are grounded separately to the frame using a bolt that holds the bumper on.

at one point one of them wasnt working, bad ground connection. and then at another point, neither worked, bad hot lead off the battery. make sure you check your ground and positive. i wouldnt assume the lights bad. double check your connections before you say the lights bad

oh and if you run them is series you wont see top performance out of your lights because there will be twice the resistance that you'd have in a parallel setup.
that is more or less how they are wired (lower gauge and fuse) but physically the same.


I guess I will try putting one of the other ones in its place and buy antoher.
 

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you may also wanna try just holding the light in your hand while running a positive and ground directly to your battery to double check to make sure its actually dead. unless youre already sure its dead then nevermind
 

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Discussion Starter #14
yep. tried it . it drew a HUGE spark and no light.

I have 3 others. they don't AND they light up.

i think the multimeter showing a short through the LED, in both directions seals it as a faulty unit. sux it only worked for like 3 minutes of burn time.
 
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