lighting issue

recently i lost power to the tail and brake light. If I apply direct power it works so it is not the unit. Does anyone know if there is a way to bypass the wiring that goes into the cdi. I.E. Pulling power say from the headlight. Which works.

Year model would be helpful.....don't you think?


My advice is to get a manual and work backward from the tail light to find where the problem is.  If both the brake and tail are out, the problem may be no more than a ground on the lamp assembly that has opened.  Jerry rigging or wiring around things is rarely advisable, and the wiring leading to the CDI really has very little to do with your lights.


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Sorry was in so much of a hurry to put up the problem failed to detail what bike as pointed out, it is a 2007 WR450F. Looking at the wiring there is a threeway plug that leads from the tail light to the CDI if memory serves me correctly.

OK, that's one of the later ones with the LED tail lamp; no brake light. 


Check for power at the dark green lead that feeds the lamp.  If none, go to the connector at the CDI and check there.  Also try feeding 12v to the dark green (with the lead disconnected) and see if the lamp lights.

Thanks for your response Grayracer513 however this one does have a brake light on the led there are three wires coming out of a plug black, blue and yellow that feed to the taillight. With the black still connected I have taken direct power( from battery) to both the Yellow and blue and the led works. Which has got me confused on a possible earth breakage. Thanks for all the help.

A combination of no power to the dark green, so have run a bridging wire. And part of the led, tail light burnt out.

All sorted. New tail light and bridging wire and back to normal.

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