Yamaha JW-II Service Manual page 37

Battery
•
Failure analysis of the battery control unit
•
The capacity cannot be displayed.
•
The battery cannot be charged.
If either of the above instances occurs, follow the procedure below to judge the failure of the
battery control unit:
1. The capacity cannot be displayed.
<Diagnosis procedure>
Replace the
Charge the
Is the case
Is the PCB lead
disconnected, or a connector
defective or disconnected?
2. The battery cannot be charged.
Carry out the diagnosis described in the later section called "• Failure diagnosis for the charger".
YES
fuse
20 V or less
battery
NO
broken?
NO
Start
diagnosis
Is the fuse
blown?
NO
Drop in battery
voltage
20 V or more
Has a
switch on the PCB
been pressed?
YES
Is the power
supply OK?
YES
The battery control unit has broken down.
Contact the Service Center for consultation.
34
Battery Functions