Chamberlain LiftMaster LA412 Owner's Manual page 43

SYMPTOM
Gate opens but does not
close.
Gate does not close
automatically with Timer to
Close enabled.
Alarm constantly sounds
for 5 minutes. Sounds
whenever a command is
issued.
Alarm is beeping 3 times on
a command.
Gate runs too slow.
Gate 2 closes before Gate 1.
Alarm beeps when running.
POSSIBLE SOLUTION
• An open input is continuously activated. Check the open loop or vehicle probe to
make sure they are clear of objects. Verify connections and operation for these
devices.
• Low battery. Measure the voltage across the battery. Voltage should be above
11.5Vdc. Replace battery if required.
• (Optional Accessory) Entry system output is connected to the OPEN input, and is
"stuck" opening. Verify entry system connections and operations.
• Obstruction blocking close photo eyes, shadow loop, or safety loop. Check eyes for
alignment and verify all connections and operation for safety devices.
• (Optional Accessory) Close safety edge is damaged or on an obstruction. Verify
operation and connection of close edge.
• Verify that the Timer to Close is ON and adjusted to desired delay.
• Gate opened by a force obstruction reversal. Check the Diagnostic LED and clear
gate path of any obstructions.
• The Interrupt loop or Shadow loop is obstructed (optional accessories).
• Obstructed close safety sensor or safety edge (optional accessory). Check
connections and operations of safety devices.
• Low battery. Measure the voltage across the battery. Voltage should be above
11.5Vdc. Replace battery is required.
• An open input is continuously activated. Check the open loop or vehicle probe to
make sure they are clear of objects. Verify connections and operation for these
devices.
• (Optional Accessory) Entry system output is connected to the OPEN input, and is
"stuck" opening. Verify entry system connections and operation.
• Operator in "Party" mode after RESET button pressed while at the OPEN limit. Use
a remote or the SBC to close the gate and reopen it. Verify that the
TIMER RUNNING LED is flashing.
• Double entrapment occurred. Two successive obstructions were encountered while
moving the gate. Press the RESET button and ensure that the gate path is clear of
all obstructions. Check the FORCE setting to make sure it is properly set.
• Low battery. Measure the voltage across the battery. Voltage should be above
11.5Vdc. Replace battery if required.
• Open and Close Limits are set too close together. If the Open and Close Limits are
set within the ramp down distance of each other, the gate will run at slow speed all
the time.
• The gate is starting within the ramp down distance from the Open or Close Limit.
Gate will run slow to limits if motion is started within the ramp-down distance from
the limit.
• Lock/Bipart Delay not set. Slide the Lock/Bipart Delay switch to ON. Verify that
Gate 1 starts moving first on open and last on close.
• Gate is excessively heavy or hinges are bad. Verify that the gate is within the
ratings for this product. Disconnect the arms and verify that both gates swing easily.
Lubricate or replace hinges as necessary.
• Gate is unbalanced. Disconnect the arms and verify that both gates swing easily in
both directions. If the gates are harder to move in one direction verses the other,
the gate is not properly balanced and the hinges must be adjusted.
• Bad motor connection. Check the motor wires and connections for possible loose or
corroded terminals.
• Low battery. Measure the voltage across the battery. Voltage should be above
11.5Vdc. Replace battery if required.
43 Operation and Maintenance