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Part 4: Troubleshooting
4-1
1. TROUBLESHOOTING
1.1 No Power
This projector provides a function which can be specified a defective area simply by
indicating the LEDs on the control panel. Connect the AC cord and press the Power
button once and then check the LED indication.
●
When all of LED indicators are not lighting,
the symptom indicates that the primary
power supply circuit does not operate properly. Check the power primary circuit
and parts as follow;
• AC cord
• F601 (Fuse)
• Power board
• SW902 (Thermal sw.) .............................short in normal
SW902 opens when the surrounding temperature of the switch exceeds 90°C.
●
When the WARNING (red) and POWER (red) indicators are flashing,
the symptom
indicates that the projector detected an abnormal temperature risen inside the
projector. Check the air filters and remove the object near the intake and exhaust
fan openings, and wait until the POWER indicator stops flashing, and then try to
turn on the projector.
The internal temperature is monitored by sensor ICs, IC2801, IC2831 and
IC2861 on the Main board.
●
When the WARNING indicator lights red,
the symptom indicates that the projector
detected an abnormality in the cooling fan operation or in the power supply
secondary circuits. Check fan operation and power supply lines, and the driving
signal status.
The P_FAIL signal (Error: L) is sent to pin 48 of IC801<SUB CPU> when the
abnormality occurred inside the projector, and then the IC801 sends the shut down
signals, 5V_SW and LAMP_BST_SW, to the power supply circuit to stop the
operation.
• An abnormality occurs on the secondary power supply;
Check power supplies 15.5V, S15.5V, S6V, S-5V. P_FAIL signal becomes
“Low” when the abnormality occurs on any of the power supply lines.
• An abnormality occurs on the fan control circuit;
Check FN901, FN902, FN903, FN904, FN905, FN906 and peripheral circuit.
Check Q67P, D67P, Q68P, D68P and peripheral circuit (Over voltage
detection circuit).
Содержание D78-5452
Страница 9: ...Part 1 General Information ...
Страница 25: ...Part 2 Repair Information ...
Страница 43: ...Part 3 Adjustment ...
Страница 66: ...Part 4 Troubleshooting ...
Страница 77: ...Part 4 Troubleshooting 4 11 4 IC BLOCK DIAGRAMS AD8075 Selector IC201 AN7513 Audio Output IC5601 ...
Страница 78: ...Part 4 Troubleshooting 4 12 AN5870 RGB SYNC SW IC1201 IC5201 BA7078 Sync Separator IC5341 ...
Страница 80: ...Part 4 Troubleshooting 4 14 CXD3536 LCD Driver IC401 FA5502 P F Control IC621 ...
Страница 81: ...Part 4 Troubleshooting 4 15 M62392 M62393 D A IC6271 IC281 ML60851 USB Driver IC9801 ...
Страница 82: ...Part 4 Troubleshooting 4 16 STR Z2156 Power Switching Control IC631 TB1274 Video Decoder IC3101 ...
Страница 83: ...Part 4 Troubleshooting 4 17 TC90A69F Y C Separator IC2101 ...
Страница 84: ...Part 5 Parts Catalog ...
Страница 85: ......
Страница 99: ...Part 6 Electrical Diagrams ...