Sharp HR-MB3 Service Manual page 29

Startup (AC adaptor)
The LOADING screen does not go to the initial
screen at startup.
Yes
Is voltage applied to pin 15 of IC400 ?
Yes
Is voltage applied to TL415 ?
Yes
Is voltage applied to TL412 ?
Yes
Is voltage applied to TL414 ?
Yes
Check peripheral circuits of IC100, IC500.
Startup (battery)
The LOADING screen does not go to the initial
screen at startup. ?
Yes
Perform checks with the ENTER key pressed.
Is voltage applied to pin 15 of IC400 ?
Yes
Is voltage applied to pin 3 of IC404 ?
Yes
Is voltage applied to TL415 ?
Yes
Is voltage applied to TL412 ?
Yes
Is voltage applied to TL414 ?
Yes
Check peripheral circuits of IC100, IC500.
No
The charging mode starts.
No
Check voltage on all pins of IC400.
No
Is voltage applied to pin 3 of IC404 ?
No
Check voltage on all pins of D401.
No
No
Is voltage applied to pin 3 of IC401 ?
No
Is voltage applied to pin 3 of IC403 ?
No
No
The initial screen starts.
No
Check voltage on all pins of IC400.
No
Check Q403, D402, and D404~D406.
No
Check peripheral circuits of IC404.
No
Check peripheral circuits of IC401.
No
Is voltage applied to pin 3 of IC403 ?
No
7 – 2
Yes
Check peripheral circuits of IC404
Yes
Check peripheral circuits of IC401.
Yes
Check peripheral circuits of IC403.
Yes
Check peripheral circuits of IC403.
HR-MB3