Panasonic SJ-MJ88 - Manual (Page 33)

Main unit’s keys LCD display position and letters
After the third key is pressed, the second digit displayed
will change from “ ” to “O ”.
VOL+ After the second key is pressed, the third digit displayed
will change from “ ” to “O ”.
VOL-
HOLD OFF The first digit displayed will change from “ ” to “O ”.
5. After all keys have been pressed and there is no abnormality, “T OOO ” will
be displayed.
6. Perform below voltage check about the keys come under if it is not displayed
“T OOO ”.
Main unit’s keys Check points ON OFF
HOLD TP428 0V 2.2V
IC201 48pin 0V 2.2V
TP421 1.13V 2.2V
TP421 1.69V 2.2V
VOL+ TP421 0V 2.2V
VOL- TP421 0.58V 2.2V
Note:
Refer to “10. Printed Circuit Board Diagram” for the test points.
7. Remove the battery when you exit from this mode.
7. Troubleshooting Guide
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