Chosen Solution
Cannot power on my keyboard with batteries. Has always worked fine with ac adaptor. All batterires aligned correctly and just bought new. Tested them with digital clock and it powers on.
Bad battery connector or broken wire or contact inside, jumper battery power to a portion of the circuit board beyond where the battery wire first makes contact or use a volt meter and trace your power to see if there is a voltage drop no allowing full battery power to the correct components. Is there a fuse for external power and also a fuse for battery power?
