Battery drains down after not using for a few weeks. This is on a 2006 Yamaha 50 HP 4 stroke. With the motor off and the key out of the ignition, I put a current meter in series with the charging wire and the battery pos terminal, I read 27 mA of DC current. I don't have the wiring diagram for this motor. Does this charge wire come directly from the rectifier? Could this be a diode with high leakage? Or just normal?