InFocus LP340B Service Manual page 94

Replace
Power Supply.
Replace
Controller board.
Note:
Color wheel must also be running
for a good 'lamp enable' signal.
The color wheel is very hard to hear in
these projectors, but it's failure is
almost always the cause of bad voltage
from the controller board,
so controller replacement at this point
is appropriate.
*These fans have a feedback sensor line that
disables the ballast and lamp.
LP340/340B/350 Service Manual
No Lamp
(continued)
Does
'lamp enable'
measure 5 volts?
(see Controller
Voltage Diagram)
No
Are
power supply
voltages good?
No
(see Controller Voltage
Diagram)
Yes
Are
both visible
Yes
fans
running?*
Replace
fan assembly.
Bad ballast.
Yes
Replace Power Supply.
Sub good fan
(plug in the good
No
fan without
installing it)
Does the good
No
fan run?
Yes
Replace Controller board.
(bad voltage to fan)
94