Chamberlain MR850 Garage Door Opener User Manual


 
T
ROUBLESHOOTING
1. The opener will not operate from either the
A
CTIVATION button or the transmitters :
Does the opener have electric power? Plug a lamp into
t
he outlet. If it does not work, check the fuse box.
Have you disabled all door locks? Review installation
instruction warnings on page 1.
Is there a build-up of ice or snow under the door? The
door may be frozen to the ground. Remove any
r
estriction.
The garage door spring may be broken. Have it
replaced.
2. Opener operates from the transmitter, but not
from the wired wall control (optional accessory):
Is the wall control lit? If not, reverse the two wires. If
the opener runs, check for a faulty wire connection at
the wall control, a short under the staples, or a broken
wire.
Are the wiring connections correct? Refer to wired wall
control instructions.
3. The door operates from the ACTIVATION button
or wired wall control, but not from the wireless
wall control or transmitter:
If the wired wall control is installed and it is flashing,
ensure the lock feature is off.
Program the opener to match the transmitter code.
(Refer to section 19). Repeat with all transmitters.
4. The transmitter has short range:
Change the location of the transmitter in your car.
Check to be sure the antenna on the bottom of the
opener extends fully downward.
Some installations may have shorter range due to a
metal door, foil backed insulation, or metal garage
siding.
5. The garage door opens and closes by itself:
Be sure that all transmitter push buttons are off.
If the wired wall control (optional accessory) is
installed, remove the bell wire from the wired wall
control terminals and operate from the ACTIVATION
button or transmitter . If this solves the problem, the
wired wall control is faulty (replace), or there is an
intermittent short on the wire between the wired wall
control and the opener.
Clear memory and re-program all wireless wall
controls and transmitters.
6. The door reverses and stops before opening
completely:
Is something obstructing the door? Is it out of balance,
or are the springs broken? Remove the obstruction or
repair the door.
7. The door reverses for no apparent reason and
opener lights blink for 5 seconds after reversing:
Check the Protector System
TM
(IR Beams), if
installed. Correct alignment if the red light on the beam
is solid.
8. The door opens but will not close or reverses
while closing:
Is something obstructing the door? Pull the manual
release handle. Operate the door manually. If it is
unbalanced or binding, call a trained door systems
technician.
Clear any ice or snow from the garage floor area where
the door closes.
Repeat the limit and force setting in section 13 &14.
Repeat safety reverse test after adjustments.
9. The opener strains to operate door:
The door may be out of balance or the springs may
be broken. Close the door and use the manual
r
elease to disconnect the door. 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 a trained door systems technician.
1
0. The opener motor hums briefly, then will not
work:
Check that the door is not in manual release mode
(refer section 8).
The garage door springs may be broken. See above.
If the problem occurs on the first operation of the
opener, door may be locked. Disable any door locks.
11. The opener will not operate due to power
failure:
Use the manual release handle to disconnect the
door. The door can be opened and closed manually.
When power is restored, re-engage the opener (refer
section 8).
If a Standby Power Unit is connected, the opener
should be able to operate up to 20 times without
power.
12. Setting the limits manually:
a. Check that the opener is handed correct (refer
sections 11 and 13).
b. Press and hold the LMT button until the orange
indicator light starts flashing slowly then release.
c. Press the LMT button to move the door UP or the
LRN button to move the door DOWN until the door
reaches the desired UP limit. Ensuring there is
enough clearance for your vehicle.
d. Press the ACTIVATION button. This sets the UP limit
and begins closing the door. Immediately press
either the LRN or the LMT button. The door will stop.
Adjust the desired DOWN limit using the LMT and the
LRN buttons. Check to be sure the door is fully
closed without applying excessive pressure to the
door curtain. Press the ACTIVATION button. This sets
the DOWN limit and begins opening the door. NOTE:
If neither the LMT or the LRN button is pressed, the
door will reverse off the floor and the DOWN travel
limit will be set automatically.
e. Open and close the door with the ACTIVATION
button, transmitter or wall control 2 or 3 times.
If the door does not stop in the desired UP limit or
reverses before the door stops at the DOWN limit,
proceed to Setting the Force (refer section 14).
If the door still does not stop at the desired limits is
something obstructing the door? Disengage the
opener. Open and close the door manually. If it is
unbalanced or binding, call a trained door systems
technician.
If the door stops at both the desired UP and DOWN
limits, proceed to Setting the Force.
16