41
Leica ST4020
7. Troubleshooting
7.3 Fault detection and correction list
Issue
Possible cause
Corrective action
• The instrument cannot be
started up
The power supply cord is
not plugged into wall outlet
properly.
•
The power supply cord is
not plugged into the stainer
properly.
•
The power supply in the in-
strument is defective.
Check the cable connections
at both ends, replace the
power supply cord if neces-
sary.
•
Inform Technical Service.
• Display appears blue, but no
text is visible.
• The contrast may have to be
adjusted again.
• The control board in the in
-
strument is defective.
• Adjust the contrast as de
-
scribed in
Chapter 5.3
.
•
Inform Technical Service.
• Unit powers up, but the
transfer mechanism does
not initialize.
• The main mechanism is
jammed.
• The motor seems to turn, but
the Lift Bar does not move
because a belt is worn or
broken, or a set screw on
the motor has come loose.
• Check for visible external
obstruction and remove as
necessary.
• The motor does not turn.
• Motor or control board
de-
fective.
•
Inform Technical Service.
• Keypad does not respond to
key presses
• The keypad or the control
board is defective.
•
Inform Technical Service.
