Electrical problem need help engine starts but soon as I use

[good samaratan]

Electrical problem need help touch break or switch on lights this just kills ignition let go of front break ignition comes back on engine starts fine, but soon as break light or lights come on bike engine just dies as if just hit killswitch,


its a aprillia futura 2002

[hmmmnz]

hmmm thats a toughie, they all share a common feed, and connector block,
but to me it almost seems like when you are using the brake or headlight that you are taking the power away from the coil,
my guess is the alternator is buggered, as i don't think there is any way for the circuit to become open just by turning on a light, (saying that the contacts on the kill switch might be dodgy and that little volt drop when you use the electriciary elsewhere could be enough to make the contact not work)
i would check that the alternator is generating enough, measure the voltage at the battery running and stoped (the bike not you )
or (some people dont recomend this) while the bike is running disconnect the battery (don't short it out on the frame) if the bike stops then the alternator is poked.

any one else got any ideas????
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[good samaratan]

i have new info if i take out the rear brake bulb so there is no contanuaty through the bulb its fine as soon as i replace the bulb the engine stops and there is no power to dash

[finpos]

Here's a mad idea - try a different bulb

finpos.

[good samaratan]

that was the first thing i tried !

[Barry_M2]

Bad earth somewhere I suspect.
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[hmmmnz]

ok, hmmm, trace the brake/tail light wires back to the first connector,
there should be 3 wires one that powers the tail light one thats the brake light and the last one is the earth,
check the connector and make sure there is no short circuit there or around that area,
if not find which is causing the fault, the brake or the tail light.
to do this, first make sure you have continuity on the earth wire, by testing it to the main earth on the battery or frame(this could quite possibly be the problem) next get some bits of wire push it into the connector , and then up to the bottom of the bulb, you will have to hold a bit of wire to the side of the bulb and have it connected to earth (3 hands would come in handy, or solder the wires to a bulb to make a test light ) once you have decovered witch one of the either tail or brake lights is causing the problem you'll be 1 more step closer to solving your wee problem
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[neeeel]

I had this problem with my RS125. Turns out the battery was running low because the charging system wasnt working properly. When i put a new fully charged battery in, it worked fine.... until that one had run low too, then every time i pressed the brake, engine would stop. Either your regulator/rectifier is knacked, or else there is a dodgy connection to or from the rectifier, or, as someone else says, ur alternator is fecked

[good samaratan]

yep it is the brake light i have taken the pins from the conector,
and replaced them one at a time untill i found the one that caused the problem,
but i can not see what is wrong with it now i have a problem with the start button i think
i am tied and fed up going to bed

thank u all for help

[good samaratan]

i am getting a new battery tomorrow