Question about 1999 Yamaha TDM 850

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My headlight is not very bright I have changed the bulb and checked the voltage and it shows 11.8v with the engine running I am not sure if this is ok

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  • Alan Connors Oct 18, 2013

    hi i get 13.8v at the headlamp connector but when i connect the headlamp and turn it on the volts drop to less than 12v with the engine running and the headlight is more like a side light its very dim



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Hi,the voltage at the battery with engine running should be around 13.8 volts.There could be any number of reasons as to what the problem is.Check the battery connections, they may be loose or corroded both on the battery and in the case of the earth or negative connection,check the frame connection.

Posted on Oct 18, 2013


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