3-11
MAIN PART
MAIN ELECTRICAL TROUBLESHOOTING GUIDE
No power on
by ADAPTOR
A
Replace ADAPTOR
NO
YES
1. POWER (DC-DC CONVERTER) CIRCUIT
Is ADAPTOR
out 9.5V
Replace D606
NO
NO
YES
YES
Is D606 OK.
Replace U202
Replace U401
Replace JK902
No +3.3V
No +5V
No LCD power
No +18V
YES
YES
Is U202
3.3V OK?
NO
Replace U401
Is U401
3.3V OK?
YES
No power on
by BATTERY
A
Replace BATTERY
NO
YES
Is
BATTERY OK?
YES
A
Summary of Contents for DP270B
Page 15: ...3 6 MEMO ...
Page 17: ...3 9 3 10 PRINTED CIRCUIT DIAGRAM TOP VIEW BOTTOM VIEW MEMO ...
Page 34: ...3 27 2 WIRING CONNECTION DIAGRAM 2 MAIN PCB KEY PCB MAIN PCB Key PCB ...
Page 51: ...3 55 3 56 1 MAIN P C BOARD TOP VIEW PRINTED CIRCUIT DIAGRAMS ...