-44-
No power
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).
- 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), Line filter board, Power board,SW902 (Thermal fuse)
SW902 opens when the surrounding temperature of the fuse exceeds 128°C.
This projector provides a function which can be specified a defective area simply by indicating the LEDs. Connect
the AC cord and press the button once and then check the LED indication.
- When the WARNING (red) and ON(G)/STANDBY(R) (red) indicators are blinking, the symptom indicates
that the projector detected an abnormal temperature risen inside the projector. Check the air filter and remove the
object near the intake and exhaust fan openings, and wait until the ON(G)/STANDBY(R) indicator stops blinking,
and then try to turn on the projector.
The internal temperature is monitored by sensor ICs, IC8801 on the Temp Sensor 1 board, IC8811 on the Temp
Sensor 2 board, IC8821 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 PFAIL signal (Error: H) is sent to pin 143 of IC401<DLP DATA PROCESSOR> when the abnormality oc-
curred inside the projector, and then the IC401 sends the shutdown signal, LAMPDC_ON, to the power supply
circuit to stop its operation, and signal LAMPSYNC is supplied to the lamp ballast board via SW901<lamp cover
switch> to stop operation of the lamp circuit. The LAMPSYNC signal is output from pin 98 of IC401 as the name
of LAMPCTRL signal.
An abnormality occurs on the secondary power supply;
Check power supplies 12V, S-5V, 16VF, 16VA. The PFAIL signal becomes “High” 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 16VF and peripheral circuit.
If any of the fans has an error, the fan lock signal drives Q7891 becomes "High". As the result, signal PFAIL_
FAN becomes Low. This error signal is supplied to the P-Fail logic ICs and it is finally supplied to the pin 143 of
IC401 as the PFAIL signal.
An abnormality occurs on the drive signals;
The table below shows the driving signal of each power supply.
SW901
Lamp cover switch
Driving signal IC output Pin No. I/O Level Swich/IC Power/Circuit
PWR_SW_LAN
IC401
39 O H Q8372 3.3V_LAN
PWR_CTRL O H Q1482 P1P2V_EDRAM
12V_AUDIO_SW 310 O H Q5101 12V_AUDIO
AUDIO_PWR_ON 378 O H Q5661 16VA
POWER_SW_B IC4501 16 O H
IC5631
Q5651
S-5V
S12V
S16VF
LAMPDC_ON IC401 305 O H
IC621
PC661
PFC
L A M P S T A T 276 I H IC401 Lamp ballast
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