Lamp Abnormality - Sanyo PDG-DET100L Service Manual

Troubleshooting

Lamp Abnormality

■ The Lamp Driving Circuit
AC
K6A
F901
SW901 POWER(AC)
FUSE
MAINS
SWITCH
BALLAST_AC1
BALLAST_AC2
IC4401
LAMP2_ON
COLOR
MANAGEMENT
FPGA
LAMP2_TXD
<EP3C40F484>
LAMP1_ON
LAMP1_TXD
IC1801
I/O
EXPANDER
<TE7783>
IC301
SYSTEM
CONTROL
<PW392>
NOTE :
■ At first, the high-voltage pulse (about 8KVp-p) is generated between the
lamp electrodes to generate glow discharge. Then dielectric breakdown
occurs, finally glow discharge comes to arc discharge.
■ After projector turned on, 30 seconds are required until the light output
stabilizes.
■ After the projector is turned off, the cooling fans operate for 90 seconds to
cool down the lamp and reduce gas pressure inside the lamp.
NOTE :
Switch
Lamp Cover
■
Make sure that the lamp cover is mounted correctly. If not or the lamp cover
removed, the lamp does not light for safety.
Check the boss of the lamp cover and the lamp cover switch (SW902).
SW902 -- open : Abnormality
■ Thermal Switches
When the internal temperature near the lamps reaches near 80ºC, the
temperature switches open and 12V is not supplied to PFC1-2 board, also
the Power fail signal "PF_POWER" bocomes "Low".
SW903 - SW904 -- open : Abnormality
■ POWER (green) LED indicates lamp monitor operation
LED off: Lamp is being cooled.
LED on: Lamp is being lit or already cooled down.
K6B
PFC12V
PF_POWER
K6C K66B
POWER(DC)
PFC_ON
ST_SW
K66L
K8B
LAMP2_RXD
LAMP1_RXD
DC_ON
Check that the lamp power
drive signals (PFC_ON1,
PFC_ON2) are correct.
Power-On: H
31
CN4
CN1
12V
CN6
K66N
PFC1-2
PFC_ON1
CN3
PFC_ON2
IC4731
IC4701
SS3.3V
PFC_ON
ST_SW
IC5808
CPU : ---- Lamp monitor operation ----
■ The CPU performs an input check by the lamp monitor
pin (LAMP_RX).
■ When the "H" signal continues 1 second or more con-
tinuously, the CPU judges the state to be abnormal.
■ When it has detected abnormal condition, the CPU
turns off a projector compulsorily. And the CPU sets up
the cooling time for 90 seconds.
■ The projector cannot be turned on during a cooling
time.
-135-
Check that the lamp on/
off signals (LAMP1_ON,
LAMP2_ON) are correct.
Lamp-On: H
X1A X3A LAMP1
LP901
BALLAST1
X2A
X1B X3B
LAMP2
LP902
BALLAST2
X2B
K8L K8Q
Q4731
Q4701
K8Z
LAMPA_1_ID
LAMPA_2_ID
LAMPA_3_ID
K8Y
LAMPB_1_ID
LAMPB_2_ID
LAMPB_3_ID
If the Lamp ID board is not mounted
securely, the warning message will
appear on the screen and some func-
tions may be disabled.
LAMP ID
LAMP ID
ID I/F 1
ID I/F 2