奇
菱
光電股份有限公司
Chi Lin Optronics Corp.
Doc. No
CS-72601
Version A3
Title
CHT-726 Level 1 Service Manual
Page
11 / 75
5. Troubleshooting
You use the Troubleshooting section to diagnose problems with projector. You can refer to a
variety of symptoms for troubleshooting. Each symptom leads you trough a series of steps that
will ultimately result in a solution. The solutions begin with the most simple and progress to the
most complex.
In addition to the Troubleshooting Table, you can also check internal voltages and signals to
diagnose a defective part by Block Diagram.
5.1 Troubleshooting Table
Symptoms Possible
Cause
Countermeasures
Blue LED doesn’t light up
The cable from the keypad to
control board does not connect
well.
The cable from control board to
power module doesn’t connect
well
The keypad malfunction
The control board defective
The power module malfunction
Check the connection of the cables
If the projector illuminates after
pressing the power key, please replace
the keypad.
Replace the control board.
Replace the failed power module
Remote controller failure
Batteries are dead
Remote controller malfunction
IR sensor is malfunction
Replace the batteries
Replace the remote controller
If the remote works fine, then test the
front and rear IR sensors, if the front
IR sensor fails, replace the control
board. If the rear IR sensor
malfunctions, replace the RS232
board.
The blue LED and the over
temperature indicator flash
alternately
The cable for the front/rear
thermal sensor doesn’t connect
well.
The front/rear thermal sensors
malfunctions
Reconnect the cable to connector.
Replace the abnormal front/rear
thermal sensor
The sequence is two blue
LED blink followed by one
red indicator blink
The wire for fan doesn’t connect
well
The rear Axial Fan failure
The front Axial Fan failure
The blower fan failure
Reconnect the wire to connector
Replace the malfunction fan
(front/rear/blower fan).
All three fans do not rotate.
The control board fails
Wrong firmware for the control
board.
Replace the control board.
Please contact CLO for the firmware
update on the control board.
Color wheel does not spin
after the projector power on
The wire from the power module
to the formatter board does not
connect well
The 4 Pin FFC doesn’t well
connect the color wheel and the
Check the wire
Check the connector pins on connect
board.
Remove the connect board from the
video module and disconnect the wire