5.3 Trouble Shooting
Have a good VOM meter to check voltages and continuity. A Meg-Ohm meter capable of checking
up to 500 meg-ohms of resistance is necessary to properly check the integrity of the ground loops.
When a malfunction occurs, isolate the problem to one of three areas: 1) the operator, 2) the loop
system, 3) the keying devices. Use caution when checking high voltage terminals, motor
capacitor and the motor.
1. Check the input indicator LEDs. They should only come ON when a keying device (card
reader, push button, etc.) is activated. If any of the input LEDs are ON continuously, this
will cause the gate operator to hold open. Disconnect the keying devices one at a time
until the LED goes OFF.
2. Check any external secondary entrapment protection devices. Any short or malfunction
in these devices can cause the gate operator to stop or to hold open.
3. A malfunction in a loop or loop detector can cause the gate operator to hold open, or to
not detect a vehicle when it is present over the loop. Pull the loop detector circuit boards
from the loop ports on the operator circuit board. If the malfunction persists, the problem
is not with the loop system. For more information on trouble shooting loops and loop
detectors, refer to your loop detector instruction sheet and to the DoorKing Loop and
Loop Detector Information Manual.
4. Check to be sure that there are no shorted or open control wires from the keying devices
to the gate operator. If a keying device fails to open the gate, momentarily jumper across
terminals 1 and 5 on the gate operator circuit board. If the gate operator starts, this
indicates that a problem exist with the keying device and is not with the gate operator.
5. If a three-button control station (open-close-stop) is connected to this gate operator,
check for proper wiring. Only a DoorKing three button control station (P/N 1200-006) can
be used with this gate operator. Others will cause a malfunction.
6. Check the high voltage supply. A voltage drop on the supply line (usually caused by
using too small supply voltage wires) will cause the operator to malfunction. Refer to the
wire size chart in section 2.1.
TROUBLESHOOTING
SYMPTON POSSIBLE SOLUTION(S)
Operator will not
run. Power LED is
OFF.
• Check that power to the operator is turned ON.
• Transformer may be overheated. Turn power off and allow board to cool for several
minutes then retest. Check for low 120 VAC power and low voltage shorts.
• Check for 120 VAC at terminals 18 and 19. If voltage measures 0, check power. If voltage
measures OK, check the terminal strip or replace the circuit board.
Operator will not
run. Power LED is
ON.
• If a photocell is used as a secondary entrapment prevention device, check to be sure that
the beam is not blocked.
• Momentarily jumper terminal 1 to terminal 5. If the input LED does not come ON, check
the terminal strip or replace the circuit board. If LED does come ON, proceed to next
steps.
• Be sure that the chain is not too tight. A too tight chain may cause the operator to stall.
• Turn power switch OFF and remove the control board.
• Place a jumper wire from terminal 18 terminal 17. CAUTION – HIGH VOLTAGE. Turn the
power switch on. The motor should run. Turn the power switch off and remove the
jumper.
• Place a jumper wire from terminal 18 to terminal 16. CAUTION – HIGH VOLT AGE. Turn
the power switch on. The motor should run in the opposite direction. Turn the power
switch off and remove the jumper.
• If the motor runs in both steps above, replace the control board. If the motor does not run,
or runs in only one direction, problem can be a bad motor, motor capacitor, wire
connections from the control board to the motor or a bad control board.
9210-065-H-8-08 Page 47