Help with LEDs
#1
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I first like to say thank you to everyone in the Rennlist family. I always use Rennlist for help and usually have good luck using the search system, but this I had no luck finding my answer. So now i am asking if anyone has had this problem, Here is what i am having a problem with, I replaced all the regular bulbs with LEDs and they looked great, but when i stepped on the brakes with lights off and key on the brakes came on and so did the front parking and marker lights they were on the dim side but still on, if I remove the LED brake light bulbs that are 1157 style it does not happen if i put the left one in the left side parking and marker come on and same for right side if i put the right one in. I feel the brake light LEDs are back feeding. At this time i do not have the regular bulbs to try. So if anyone else has had this problem any help would be great and thanks
#3
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#4
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Interesting situation. Did you get cheap led's out of Asia? Maybe try to temporarily install a diode on the + side to see if it'll change.
Be careful not to create a short when you fiddle with it.
Ed
Be careful not to create a short when you fiddle with it.
Ed
#5
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the front lights are receiving a small voltage when you step on the brakes?
what happens if you unplug the rear brake light, and step on the brakes? do the front lights still come on?
I don't know the brake light circuitry but that seems really strange that the brake switch is connected to front lights. Seems like there is probably a partial short somewhere between the circuits at less than 14V, thus the dim fronts. I am guessing that the only place those wires/circuits cross is under the dash somewhere. You might try wiggling the wire harness under the dash to see if you can get the front to flicker while you have the brake pedal pressed.
others that know the electrical circuits better can probably point you in a more specific direction.
#7
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so just to make sure I understand this.
the front lights are receiving a small voltage when you step on the brakes?
what happens if you unplug the rear brake light, and step on the brakes? do the front lights still come on?
I don't know the brake light circuitry but that seems really strange that the brake switch is connected to front lights. Seems like there is probably a partial short somewhere between the circuits at less than 14V, thus the dim fronts. I am guessing that the only place those wires/circuits cross is under the dash somewhere. You might try wiggling the wire harness under the dash to see if you can get the front to flicker while you have the brake pedal pressed.
others that know the electrical circuits better can probably point you in a more specific direction.
the front lights are receiving a small voltage when you step on the brakes?
what happens if you unplug the rear brake light, and step on the brakes? do the front lights still come on?
I don't know the brake light circuitry but that seems really strange that the brake switch is connected to front lights. Seems like there is probably a partial short somewhere between the circuits at less than 14V, thus the dim fronts. I am guessing that the only place those wires/circuits cross is under the dash somewhere. You might try wiggling the wire harness under the dash to see if you can get the front to flicker while you have the brake pedal pressed.
others that know the electrical circuits better can probably point you in a more specific direction.
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#8
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often happens especially on cheaper combined led bulbs . because the rear light bulbs are combined brake and tail light bulbs and are tightly packed on to a small circuit board and unlike a incandescent bulb which has a separate filament for the brake light and the tail light, so its impossible for the current to leak into the other circuit, where as the led bulb uses the same leds for both brake & tail so you often get a small amount of current leaking into the the other circuit, ie the front side light
#9
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often happens especially on cheaper combined led bulbs . because the rear light bulbs are combined brake and tail light bulbs and are tightly packed on to a small circuit board and unlike a incandescent bulb which has a separate filament for the brake light and the tail light, so its impossible for the current to leak into the other circuit, where as the led bulb uses the same LEDs for both brake & tail so you often get a small amount of current leaking into the the other circuit, ie the front side light
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You could use blocking diodes as someone else suggested, thats probably the only way to cure it, or try using a better quality bulb although even quality bulbs can cause the same issues.
I take it from reading your post that you have fitted led bulbs into your front side/marker lights ? If you change back to normal incandescent bulbs in the front you should find you wont have the problem anymore, as they need more current than a led bulb, although I suspect you probably don't want to go back to normal bulbs as it defeats the look your trying to achieve, so diodes or someway of slightly loading the circuit to use up the small stray current so there is nothing left to make your front side lights glow
Hope you manage to get it sorted
Regards
I take it from reading your post that you have fitted led bulbs into your front side/marker lights ? If you change back to normal incandescent bulbs in the front you should find you wont have the problem anymore, as they need more current than a led bulb, although I suspect you probably don't want to go back to normal bulbs as it defeats the look your trying to achieve, so diodes or someway of slightly loading the circuit to use up the small stray current so there is nothing left to make your front side lights glow
Hope you manage to get it sorted
Regards