Craftsman 139.53491SRT Owner's Manual page 35

Situation
The door opens but
won't close:
The door reverses for no
apparent reason and
opener lights don't
blink:
The door reverses for no
apparent reason and
opener lights blink for
5 seconds after
reversing:
The opener lights...
The opener strains or
maximum force is
needed to operate door:
The opener motor
hums briefly, then
won't work:
The opener won't
operate due to power
failure:
Troubleshooting
Probable Cause & Solution
1. If the opener lights blink, check the safety reversing sensor. See page 22.
2. If the opener lights do not blink and it is a new installation, check the down force. See
Adjustment Step 2, page 29. For an existing installation, see below.
Repeat the safety reverse test after the adjustment is complete.
1. Is something obstructing the door? Pull the emergency release handle. Operate the door
manually. If it is unbalanced or binding, call for professional garage door service.
2. Clear any ice or snow from the garage floor area where the door closes.
3. Review the force adjustment procedures on page 29.
4. If door reverses in the fully closed position, decrease the travel limits (page 28).
Repeat the safety reverse test after adjustments to force or travel limits. The need for
occasional adjustment of the force and limit settings is normal. Weather conditions in
particular can affect door travel.
Check the safety reversing sensor. Remove any obstruction or align the receiving eye. See
pages 12 and 22.
don't turn on:
Replace the light bulb(s) (100 watts maximum). Use a standard neck garage door opener bulb
if regular bulb burns out.
don't turn off:
Is the Light feature on? Turn it off.
The door may be out of balance or the springs are broken. Close the door and use the
emergency release handle to disconnect the trolley. Open and close the door manually. A
properly balanced door will stay in any point of travel while being supported entirely by its
springs. If it does not, disconnect the opener and call for professional garage door service.
Do not increase the force to operate the opener.
1. The garage door springs are broken. See above.
2. If the problem occurs on the first operation of the opener, door may be locked. Disable the
door lock.
Repeat the safety reverse test after the adjustment is complete.
1. Use the emergency release handle to disconnect the trolley. The door can be opened and
closed manually. When power is restored, press the Door Control push button and trolley
will automatically reconnect (unless trolley is in lockout position.) See page 32.
2. The Emergency Key Release accessory (for use on garages with no service door)
disconnects the trolley from outside the garage in case of power failure.
(continued)
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