GT20 Control Wiring and Programming Manual
Part #C-00140
Rev. 10-7-16
10-46
Troubleshooting
Erroneous Behavior
Analysis
Possible Causes
Remedy
Drive unit fails to close
LED SE (Safety Sensor,
yellow) is lit
One or more Safety
Sensors are active
or incorrectly
cabled
X
Remove the obstacle
X
Check the cabling between
the Safety Sensor and the
control unit and eliminate any
detected deficiencies
X
Replace the Safety Sensor
X
LED SE (Safety Sensor,
yellow) is not lighted
X
LED OE (opening
command, blue) is lit
An opening
command is
pending
X
Check the cabling between
the opening element and the
control unit and eliminate any
detected deficiencies
X
Replace the Activation Sensor
Check the operating mode The operating
mode OPEN is
active
Change the operating mode
The Operating Mode cannot
be changed
Program selection keys on
the side on the side cover
are not lighted
The ribbon cable
is not plugged in
correctly, or not
plugged in at all
Check the ribbon cable and
eliminate any problems
The Operating Mode
symbol on the display is
underlined
The Operating
Mode is
overridden via
connection
terminal X110
X
Change the operating mode by
means of the external Power/
Mode Switch
X
Correct the cabling of the
external Power/Mode Switch
Notice: “If after troubleshooting a problem, and a satisfactory solution cannot be achieved,
please call Nabco Entrances at 1-877-622-2694 between 8 am – 4:30 pm Central time
for additional assistance. DO NOT leave any problem unresolved. If the door cannot
be repaired immediately, turn off the door and leave it inoperable until repairs can be
made. Advise the owner NOT to operate the door in the automatic mode until repairs are
effected. NEVER leave a door operating without all safety detection systems operational.“