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• An abnormality occurs on the drive signals;
POWER_SW signal (Power-on: H) is output from pin 1 of IC801 and input to
pin 17 of IC1881, and output from pin 3 by the name of 5V_SW.
LAMP_BALAST_SW1(Power-on: H) is output from pin 12 of IC1851 (D/A) and
supplied to the P.F Control IC, IC621, through the IC1881, Q651, and
PC643.
BALAST_AC signal (Power-on: H) is output from pin 39 of IC801 and input to
pin 11 of IC1881, and output from pin 9 by the name of BALAST_AC1.
BALAST_AC1 signal is applied to pin 2 of IC4891 and output pin 4 and then
supplied to the lamp balast unit through the Lamp Cover switch (SW901).
CHO_RXD signal at the pin 77 of IC801 is applied from the lamp balast unit.
If the abnormality occurred on the lamp balast unit, CHO_RXD (LAMP_DET)
signal becomes “High” and then IC801 shuts down the power supply circuit.
[Lamp cover switch]
Make sure that the lamp cover is mounted correctly. If not or the lamp cover removed,
the lamp does not light on for the safety. Check the lamp cover and lamp cover switch
(SW901).
Fig. 4-1
[Reset switch]
The microprocessor inside the projector may occasionally malfunction and does not
accept any controls. In this case, press the reset switch on the rear panel with a sharp
tool to restart the projector.
Fig. 4-2
Part 4: Troubleshooting
4-2
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 ...