User Guide & Service Guide
USER GUIDE
u-line.com
Troubleshooting Extended
MAIN CONTROL
The main control board is very robust and is rarely the 
cause of system issues. It is important to fully diagnose 
the board for any suspected failures before attempting 
to remove the board for replacement or service. Follow 
the guidelines below to fully test and diagnose the main 
control.
Power Fault
If the unit does not (or seems to not) power on, follow the 
ow chart below to help diagnose the issue. Before begin-
ning it is important to rst verify the unit is not simply set 
to sabbath mode.
Check Voltage 
At Wall Outlet
Verify Voltage At 
Main Control 
Voltage Input
Check Fuse F1
For Continuity
Replace 
Plunger Switch
Replace Main
Board
Replace
Fuse
Replace
Power Cord
Alert Customer 
Of Power Failure
Is the Plunger
Switch Operating
Properly?
Inspect 
Customer UI 
and Data Cable 
Connect Test Display 
Cycle Power And Check 
For Operation 
No Voltage
No Voltage
Voltage
Continuity
Operating
Not Operating
No Continuity
No
Yes
Voltage
CAUTION
!
Precautions must be taken while working with 
live electrical equipment. Be sure to follow 
proper safety procedures while performing tests 
on live systems.
PLUNGER SWITCH
A plunger switch is used to monitor door state. When the 
door is closed it comes into contact with the plunger which 
closes a circuit which turns the light and display o. When 
the door is open the plunger moves outward and opens the 
circuit. If the door is left open for longer than 5 minutes 
the switch will trigger an error code and set an audible 
warning.
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