Sanyo PLC-XF60 Service Manual page 84

Chassis Description & Troubleshooting
The cause of the NO POWER is separated into 5 items as listed below. Check with the table on previous page and
make a short list of failure. The below shows the error condition and detection parts/signals.
Error Condition, Detection parts and signals flow
Temperature failure
- IC8821 monitors temperature inside the projector and IC8841 moitors temperature arround the intake duct,
and IC8821, IC8841 send data (SCL/SDA) to pins 216 and 217 of IC801<CPU>.
- SW913 monitors temperature on the LCD panel and sends signal (TEMP_LCD) to IC801<CPU> through
IC4802<I/O EXPANDER> Error: H.
- SW914 detects abnormal temperature on the Shutter and sends signal (MS_THERMO) to pin 1 of IC9870
<NAND>. IC9870 drives Q9802 off when signal MS_THERMO becomes "High" and then the operation of
Ballast1/Ballast2 is stopped.
Lamp failure
- Ballast1 detects Lamp1 error on Lamp1 and sends signal (LAMP_SENS, LAMP1_RXD/LAMP1_ERR) to pin
167 of IC801 through IC4751<INVERTER>.
- SW902 detects Lamp1 Cover opened and sends signal (LAMPCOVER) to pic 2 of IC9870. IC9870 drives
Q9802 off when signal LAMPCOVER becomes "High" and then the operation of Ballas1/2 is stopped.
- Ballast2 detects Lamp2 error on Lamp2 and sends signal (LAMP_SENS, LAMP2_RXD/LAMP2_ERR) to pin
168 of IC801 through IC4751<INVERTER>.
- SW905 detects Lamp2 Cover opened and sends signal (LAMPCOVER) to pic 2 of IC9870. IC9870 drives
Q9802 off when signal LAMPCOVER becomes "High" and then the operation of Ballast1/2 is stopped.
Filter failure
- SS901 detects clogged on the filter (BLOW_SENS).
- SW903 detects Filter is not placed correctly and sends signal (FIL_SENS) to IC801 through IC4801<I/O
EXPANDER> Error: H.
Shutter failure
- Shutter switches detects shutter control error, and sends signals (STR1_OP, STR1_CL, STR2_OP, STR2_
CL) to IC801 through IC4801<I/O EXPANDER>. If IC801 detects abnormal operation of the shutter, the
projector is set into the standby mode after cooling down the projector.
Shutter
STR1_OP
STR1_CL
STR2_OP
STR2_CL
Power failure
- Failure detection diodes detect a power failure on the power supply circuit (detection signals see items
Power Supply and Failure Detection).
or
- Detects a fan lock on the cooling fan (detection signals see items Power Supply and Failure Detection).
If all of the LEDs are not lightning, either the safety protection circuit is operating for product safety or primary AC
power is not supplied to the POWER(AC) board.
Safety Protection Circuit
This projector provides the safety protection circuit for product safety as follows;
SW904 (Bottom Cover switch) detects that the bottom cover is not mounted correctly (SHUTDOWN1)
SW911 (Lamp1 Thermal switch) detects abnormal temperature on the Lamp1 (SHUTDOWN1)
SW912 (Lamp2 Thermal switch) detects abnormal temperature on the Lamp2 (SHUTDOWN1)
If one of the above switches detects abnormal, the switch will be opened, and the detection signal <SHUT-
DOWN1> becomes "High" to stop the operation of the primary power supply circuit.
Open Close High-Contrast
Low High High
High Low High
Low High High
High Low High
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