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Discussion Starter · #1 ·
Ok, so I just put in LED bulbs in my reverse lights and the license plate lights. It looks good, nice and bright, but one strange thing. After they're on and I turn them off, they'll blink or flash every couple of seconds. This eventually stops after like an hour or so. I dont think there's a current running through them because the car's off and there's no key in the ignition. Could I be wrong? Or is this just residual current from when they were on?
 

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This is due to the cars security system and bulb checking facility. The bulb check passes a small current through the bulbs to ensure continuity and check no bulbs are blown, this low current will not light normal bulbs, bulb it is enough to light LEDs. Any LEDs fitted to any of the external lights will flash like this, unless you fit inline resistor packs, which can be bought from most online LED suppliers. There are threads on here that explain this in better detail, but this is the basic reason for it.

Steve.
 

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This is because the resistance needs to be increased in the wiring for LED bulbs because it draws less current than the conventional bulbs; the LEDs require less wattage so the resistance needs to increase because the voltage is constant. V=I R. Because of this you get that knight rider flicker.
 

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ProBaller said:
Ok, so I just put in LED bulbs in my reverse lights and the license plate lights. It looks good, nice and bright, but one strange thing. After they're on and I turn them off, they'll blink or flash every couple of seconds. This eventually stops after like an hour or so. I dont think there's a current running through them because the car's off and there's no key in the ignition. Could I be wrong? Or is this just residual current from when they were on?
I had the same exact thing happen. Does it really take an hour for them to stop blinking? I ended up shelving mine for the time being.
 

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Discussion Starter · #5 ·
See, what I dont understand is why the amount of time they blink changes. It seems as if the length of time that they blink is directly proportional to the length of time there is power running through the bulb.

If all I need is a resister, will these work? http://superbrightleds.com/tail-brake-turn.html

It says that they have "built in current limiting resistors." I didn't do too well on the electrical portion of my physics class. 8 am physics is not a good idea fyi.
 

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stevedol said:
This is due to the cars security system and bulb checking facility. The bulb check passes a small current through the bulbs to ensure continuity and check no bulbs are blown
On mine I can actually hear a slight noise from one of the brake/taillight bulbs due to this. It is definitely coming from the bulb, sounds like the filament is vibrating when the current is turned on.
 

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i had the same problem.

the only reason i took them is out is because at night, people behind you might think you're an emergency vehicle. they blink ALL the time while the car is running, whether your lights are on or not.

i didn't think an equipment fine would be worth it, so i threw the stock ones back in.

however, having them in the brake lights isn't so bad, at least if you have your lights on a lot. i currently have red LED tail lights on the outside and white on the inside. it's a really nice effect, dark to light red across the rear.
 

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I personally like the strobing effect on mines :cheesy: Kinda looks cool. i replaced the front parking light (next to the high beam) The tail lights, license plate light, and reverse light. Really gives the car a nicer look. Since my lights are basically on all the time it doesn't bother me. And when it's parked and off, i just Arm the alarm to lock and the strobing will turn off in about 15-20 seconds. people think it's my alarm strobing and i get commented on it haha ;)
 

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dizwhoadayjohn said:
I personally like the strobing effect on mines :cheesy: Kinda looks cool. i replaced the front parking light (next to the high beam) The tail lights, license plate light, and reverse light. Really gives the car a nicer look. Since my lights are basically on all the time it doesn't bother me. And when it's parked and off, i just Arm the alarm to lock and the strobing will turn off in about 15-20 seconds. people think it's my alarm strobing and i get commented on it haha ;)
So the parking lights (194 bulb next to H7 bulb) only blinks for about 20 seconds after they are turned off?
 

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wtfwill said:
i currently have red LED tail lights on the outside and white on the inside. it's a really nice effect, dark to light red across the rear.

sounds interesting. would like to see that. got any pics?
 

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dizwhoadayjohn said:
I personally like the strobing effect on mines :cheesy: Kinda looks cool. i replaced the front parking light (next to the high beam) The tail lights, license plate light, and reverse light. Really gives the car a nicer look. Since my lights are basically on all the time it doesn't bother me. And when it's parked and off, i just Arm the alarm to lock and the strobing will turn off in about 15-20 seconds. people think it's my alarm strobing and i get commented on it haha ;)
Mine do the exact same thing in the front after I arm the alarm (strobes back and forth slowly for ~40sec). I think it looks really cool like an aftermarket kit or something. Everyone asks me about it as well.
 
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