Any - Motorcycle LED Brake/Tail/number plate light

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Mon 8 Aug 2011 15:45
Any - Motorcycle LED Brake/Tail/number plate light - Cris_on_the_gas

got a strange problem here.

Tried to fit an additional LED light for tail , number plate & brake. New unit comes with 3 wires. Blue- Brake light. Yellow Tail & number plate. Green- earth.

Strange when additional brake light is fitted then tail light extinishes but number plate light stays illuminated.

supplier doesn't seem to know much about these but has offered to replace which won't halp as it seems to be a feature that i would like to bypass

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Tue 9 Aug 2011 12:20
Any - Motorcycle LED Brake/Tail/number plate light - dieselnut

I would try connecting the new unit, once disconnected, direct to a 12v supply ( via a fuse ).

Try each light separately then both together.

Sounds to me like the new unit might be faulty.

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Wed 10 Aug 2011 14:13
Any - Motorcycle LED Brake/Tail/number plate light - Cris_on_the_gas

Yep tried that, whenever brake light filament and earth connected to brake light lead the tail light extinguises but the number plate light stays on. Both tail & number plate light use same wire. It's althought there's some sort of logic gate connected to the brake light lead that if it sees an earth of any resistance it extinguises the tail light. Replacement unit identical, unit has got E mark on so must have been approved.

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Wed 10 Aug 2011 17:17
Any - Motorcycle LED Brake/Tail/number plate light - bathtub tom

Sorry, but why do you need a tail light when your brake light's illuminated, wouldn't the brighter light of the brake light make the tail light 'invisible'?

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Thu 11 Aug 2011 12:57
Any - Motorcycle LED Brake/Tail/number plate light - Cris_on_the_gas

Because its an additional brake/tail light. Additiional light mounted above number plate so is required

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Fri 12 Aug 2011 12:52
Any - Motorcycle LED Brake/Tail/number plate light - dieselnut

Some modern bikes ( BMW for one ) have a detector circuit for the rear light. If it detects a fillament failure it diverts power to the other fillament so you still have a rear light for safety.

The LED light will apear to any detector as a blown fillament as they draw little current.

Check that both bulb fillaments are good, I found that some other make bulbs will trip this detector & had to buy a genuine BMW bulb to fix it.

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Sat 13 Aug 2011 01:33
Any - Motorcycle LED Brake/Tail/number plate light - Cris_on_the_gas

thank for the info Dieselnut, but not the problem is not quite as you described.

When this additional light is connected up the brake and tail/index lamp are wired in parallel with the existing wiring.

When the brake light wire is connected to the existing brake light wire the tail light goes out. This is without the brake light being operated. Strangly the number plate light stays illuminated. Its on the same feed wire so this is illogical.

So as per original post its although there is a logic gate on the brake light wire that is detecting a filament and earth behind it and killing the tail light.

Wierd or what ???

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