LiftMaster J door operator - Manual (Page 38)

38
TROUBLESHOOTING
TROUBLESHOOTING GUIDE
THE OPERATOR WILL
NOT RESPOND TO ANY
COMMANDS
POWER LED IS NOT ON
STOP BUTTON LED IS
NOT ON
THE DOOR WILL MOVE
ABOUT A FOOT THEN
STOP. AFTER STOPPING,
ONLY CONSTANT
PRESSURE COMMANDS
WILL MOVE THE DOOR
THE DOOR WILL MOVE
MOST OF THE WAY
TOWARDS A LIMIT THEN
STOP. AN EXTRA OPEN OR
CLOSE COMMAND IS ABLE
TO GET DOOR TO
COMPLETE CYCLE
THE DOOR WILL OPEN
SOME BUT NOT
COMPLETELY. AN EXTRA
OPEN IS ABLE TO GET THE
DOOR TO OPEN
COMPLETELY
THE DOOR WILL OPEN BUT
WILL ONLY CLOSE AFTER
A FIVE SECOND DELAY
WITH CONSTANT
PRESSURE ON THE CLOSE
BUTTON (RESTRICTED
CLOSE MODE)
a) No power supply ➤ Verify primary line voltage from power source. Green POWER LED
must be on.
b) Operator control station is wired wrong ➤ Use the OPEN, CLOSE and STOP LEDs to help check correct wiring.
Verify that the board is accepting commands by using the onboard
station. Green LED next to stop button must be on.
c) Interlock switch is activated ➤ Check Interlock(s). If more than one external interlock is present they
must be wired in series. Green LED next to stop button must be on.
d) Dial still in programming, option, ➤ Set dial to desired wiring type.
or diagnostic mode
e) Motor is malfunctioning
➤ Verify proper voltage getting to the motor (Check motor name plate).
f) Motor thermal overload tripped ➤ Check to see if motor is hot. Allow motor to cool before attempting to
move door. Cycle operator in constant pressure one full cycle open and
close to reset fault.
g) Possible accessory malfunction ➤ Disconnect all devices, reattach them one at a time testing for a failure
after each one is replaced.
h) Off Board relay may need to be ➤ When the OPEN or CLOSE button is pressed, Relay A or B LED should
replaced see wiring diagram turn on and the door should move in the corresponding direction. If
Relay A or B lights and the door does not move, off board relay may
need to be replaced (see wiring diagram Off Board Relays).
i) Possible logic board failure ➤ Replace logic board.
a) Control station not connected or wired ➤ Check wiring to control station.
correctly
b) Interlock switch
➤ Check interlock switch(es) for continuity.
a) The photoelectric sensors, edge or ➤ If the on board LMEP LED is flashing, the photoelectric sensor are
other sensing device is obstructed misaligned or not connected. Remove any obstructions, check the
or activated safety device wires for continuity and shorts.
b) The logic board thinks that the direct ➤ Unlearn the photoelectric sensors from the memory by resetting
connect photoelectric sensors are factory defaults.
attached and blocked
FAULT POSSIBLE CAUSE FIX
a) RPM sensor is not connected properly ➤ Check the RPM assembly for loose connections. Check that RPM wheel
or may need to be replaced is turning when operator is running. Check for foreign matter blocking
optical lens.
➤ Replace RPM sensor.
b) Clutch slipping ➤ Adjust clutch and verify that door is not binding.
The Maximum Run Timer is not set ➤ Manually reprogram the Maximum Run Timer (page 35).
correctly OR reset the factory defaults (page 35).
There may be a Mid Stop set ➤ Check to see if the Mid Stop LED is on. Clear the Mid Stop by turning
the selector dial to program. Press and hold the MID STOP button for
5 seconds. Return dial to desired wiring type.
To reset Open Mid Stop refer to page 33.
a) Loose secondary wiring connections ➤ Repair or replace connections or control transformer.
or a faulty control transformer
b) Hoist interlock switch
➤ Check interlock. Verify the manual release chain is not engaged.
Troubleshooting guide