brake lights question advice needed

[undercover]

stupid me my bike was blown over in the winter it's due a mot so dusted off the cobwebs

what i dont understand is my rear brake light is not illuminating from front and rear brake levers.

but when i turn my headlight on full ''not high beam'' my rear light illuminates

i first though one of the the brake switches had seized or died but no after checking the bulbs fuse box and connectors

any advice here would be great 
 
 

[rj2para (Bisto)]

The rear brake only operates via the rear brake pedal.

[rj2para (Bisto)]

The rear brake 'should' only operates via the rear brake pedal.

[undercover]

yes i understand but there is a front switch so the front brake lever activates the rear brake light.
the problem i am trying to work out is the rear light illuminates but when i press the brake pedal front/rear no additional light illuminates.

so when i dont have my headlight on and i brake there is no brake light activated.

[slug]

hi undercover,. check you have a 12v feed to switch
front and back. if so check when you operate each switch
there is a feed out from switch. this proves switchs, if they
work .would look at wiring to bulb holder in rear light.see that
you have feed there when brake switch operated if not would be wire in
between switch and light. lets us know how you get on.
cheers slug.

[kirriepete]

It's unlikely (not impossible, but ...) that both bulbs will have dropped dead, in just the same way that both switches are unlikely to fail at the same time - generally they wait until you've ordered a replacement for the other one, then fail so you get stuck with double postage charges (ask me how I know this and why I now use banjo switches!).

Soooooo ... the most likely area for a fault is in the wiring that is common to both bulbs and both switches, I'd be tempted to check for continuity along the wiring from one switch connector to the bulb holder (rear switch is closest) - if it's open circuit move one probe towards the other until you get a reading, then you've found your break. In theory, of course!

Electrickery problems can be a real 'mare to track down, but with a logical approach and a decent multi-meter you can eventually find the bad connection and sort it.

Best of luck in the hunt.

[ploddit]

I've seen bulbs forced in 180 degrees out so that the brake light illuminates all the time.

[undercover]

ok i finnaly found the problem with my rear brake lights
i have slowly lost patience with my haynes manual's electrical diagram.
the loose connection is in the green wire on the right that has a double fitting that connects the blue and black wire'
tinypic.com/view.php?pic=fyyc6&s=8#.U2Gl5KJN34h

i have crimping kit so may just replace everything thats there.
common sense i will label the wire's before i remove them.

this leads me back to the haynes manual is there a sticky on understanding electrical diagrams in the haynes manual because just for future i am lost trying to understand it.