electrical problems?

[soundbeltfarm]

i got a rotating chasing rear lightbulb for my bike.
its one of those led ones has about 12 leds in a circle and when the lights are on the lights chase earound the circle and when you use the brake they all flash on and off.
when the bike is not running and the lights are turned on they work and when the brake is applied they flash like they are meant to.
but
when the bike is running and the lights are turned on they work but if the brake lever is applied they flash once then the bulb dosnt light at all and when the brake is released no chasing lights.
if i turn the light switch off then back on again they chase around again but if i pull the brake the same happens, they die.
what will the cause be and can i remedy it.
with the bike going will that increase the current and cause it to stop with an increase of current with the brake applied.

cheers for any help.
its an old bike 86 gsxr.
when the old bulb is in it works fine.

[Jackrat]

Sounds like a dodgie earth.
Maybe!!!

[soundbeltfarm]

Sounds like a dodgie earth.
Maybe!!!

but wouldnt that make the the normal bulb not work?
or is that because the normal bulb has 2 filaments (one for the brake and one for the lights)
with the led one they are all used for the brake and lights.

[soundbeltfarm]

Sounds like a dodgie earth.
Maybe!!!

checked the earth and couldn't find nothing .
i got a multi meter but dont know how to use it on the bulb socket.
should i check to see if the voltage spikes when the brakes are applied with the engine going?

[Holy Roller]

Compare the base of each bulb do they both have two silver solder patches---

If they do then try putting the led bulb in 180 deg ie upside down so to speak and see if that works.
Check the pins that hold the bulb in place are they in the same position ie opposite each other or off set. If off set it will only work if placed in the right way round.

Check the led bulb by wrapping a stripped bare wire end around the metal base of the bulb and connecting the other end to an earth on the bike usually some metal part on the frame. use another wire connected to a live point in your wireing or to the + of the battery and touch the other end to the silver connection points on the base of the bulb in turn and observe what happens. Then place the wire across both points.
This should simulate tail lights on and then brake light on and then both tail and brake light on.

[soundbeltfarm]

Compare the base of each bulb do they both have two silver solder patches---

If they do then try putting the led bulb in 180 deg ie upside down so to speak and see if that works.
Check the pins that hold the bulb in place are they in the same position ie opposite each other or off set. If off set it will only work if placed in the right way round.

Check the led bulb by wrapping a stripped bare wire end around the metal base of the bulb and connecting the other end to an earth on the bike usually some metal part on the frame. use another wire connected to a live point in your wireing or to the + of the battery and touch the other end to the silver connection points on the base of the bulb in turn and observe what happens. Then place the wire across both points.
This should simulate tail lights on and then brake light on and then both tail and brake light on.


the bulb has offset pins.
the led works fine when the bike is off but as soon as the bike i running and i put the the brake on it flashes once then stays off and to get the bulb to work again i have to turn the light switch off then on again.
and if i pull the brake it does the same thing.

[Blakamin]

resistance.... ohms law.... I cant explain it but google might....

[Holy Roller]

checked the earth and couldn't find nothing .
i got a multi meter but dont know how to use it on the bulb socket.
should i check to see if the voltage spikes when the brakes are applied with the engine going?
:brick: miss read you post been along weekend away fishing all night and then the toy run...


Select voltage DC on the meter the blach lead or - placed on an earth the red lead or + touching either pin inside the bulb carrier with the lights on until one gives a reading note reading should be around 12.4V
Touch the other pin with the brakes on note reading
do the same with the bike running if readings are the same :spudwhat:
If readings are greater with the engine running you may have an overcharging problem starting and will need to get it looked at.