No Power - Eiki LC-WB200 Service Manual

Troubleshooting

No Power

This projector provides a function which can be specified a defective area simply by indicating the LEDs. Connect the
AC cord and press the ON/STAND-BY 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 primary power circuit and parts as follow;
AC cord, F601 (Fuse), Power board,
SW90 (Thermal sw)
- 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, IC8831, IC881 on the Main board and IC8811 on
the R/C 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), FAN_ERR_B signal (Error: L), FAN_ERR_C (Error: H) are sent to pins, 81, 145,
and 8 of IC301 <SYSTEM CONTROL> respectively when the abnormality occurred inside the projector, and
then the IC301 sends the shutdown signal, LAMP_DC_ON, to the power supply circuit to stop its operation, and
signal SCIOUT to the lamp ballast board via IC9886 and SW901<lamp cover switch> to stop operation of the
lamp circuit.
An abnormality occurs on the secondary power supply;
Check power supplies S16V, S6V, S-7V. P_FAIL signal becomes Low when the abnormality occurs on any
of the power supply lines.
An abnormality occurs on the fan control circuit;
If fans FN901, FN90 or FN903 has an error, the FAN_ERR and P_FAIL signals become "L". If fans
FN904 or FN905 has an error, the FAN_ERR, P_FAIL and FAN_ERR_B signals become "L". If fan
FN906 has an error, the FAN_ERR_C signal becomes "H", The FAN_ERR signal cut off the
SCIOUT signal which is supplied to the lamp ballast board if the FAN_ERR signal is "L".
An abnormality occurs on the drive signals;
ON_15V signal (Power-on: H) is output from pin 35 of IC301 and switches IC59,15.5VL supply circuit,
ON_3.3V signal (Power-on: H) is output from pin 53 of IC301 and switches IC561 - 1.0V, IC385 - 3.3V
supply circuits.
LAMP_DC_ON signal (Power-on: H) is output from pin 0 of IC301 and supplied to the PFC Control IC,
IC61, on the power supply board.
SCIOUT signal (Power-on: H) is output from pin 3 of IC9001 and applied to pin  of IC9886 and output
pin 4 and then supplied to the lamp ballast board through SW901<Lamp Cover SW>.
LAMP_DET signal at the pin 439 of IC301 is applied from the lamp ballast unit. If the abnormality occurred
on the lamp ballast unit, LAMP_DET signal becomes "High" and then IC301 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).
short in normal
SW90 opens when the surrounding temperature of the switch exceeds 115°C.
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