• 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
Summary of Contents for LV-7215U
Page 9: ...Part 1 General Information ...
Page 25: ...Part 2 Repair Information ...
Page 43: ...Part 3 Adjustment ...
Page 66: ...Part 4 Troubleshooting ...
Page 78: ...Part 4 Troubleshooting 4 12 AN5870 RGB SYNC SW IC1201 IC5201 BA7078 Sync Separator IC5341 ...
Page 80: ...Part 4 Troubleshooting 4 14 CXD3536 LCD Driver IC401 FA5502 P F Control IC621 ...
Page 81: ...Part 4 Troubleshooting 4 15 M62392 M62393 D A IC6271 IC281 ML60851 USB Driver IC9801 ...
Page 83: ...Part 4 Troubleshooting 4 17 TC90A69F Y C Separator IC2101 ...
Page 84: ...Part 5 Parts Catalog ...
Page 85: ......
Page 99: ...Part 6 Electrical Diagrams ...