Chamberlain 8155 - Troubleshooting; Diagnostic Chart

14
Troubleshooting
DIAGNOSTIC CODE SYMPTOM SOLUTION
Up arrow
Flash(es)
Down arrow
Flash(es)
11
The garage door opener
will not close and the
light bulbs fl ash.
Safety sensors are not installed, connected, or wires
may be cut. Inspect sensor wires for a disconnected
or cut wire.
12
The garage door opener
will not close and the
light bulbs fl ash.
There is a short or reversed wire for the safety
sensors. Inspect safety sensor wire at all staple and
connection points, replace wire or correct as needed.
13
The door control will not
function.
The wires for the door control are shorted or the door
control is faulty. Inspect door control wires at all
staple and connection points, replace wire or correct
as needed.
14
The garage door opener
will not close and the
light bulbs fl ash.
Safety sensors are misaligned or were momentarily
obstructed. Realign both sensors to ensure both LEDs
are steady and not fl ickering. Make sure nothing is
hanging or mounted on the door that would interrupt
the sensor’s path while closing.
15
Door moves 6-8" (15-20
cm) stops or reverses.
Manually open and close the door. Check for binding
or obstructions, such as a broken spring or door lock,
correct as needed. Check wiring connections at travel
module and at the logic board. Replace travel module
if necessary.
No movement, only a
single click.
Manually open and close the door. Check for binding
or obstructions, such as a broken spring or door lock,
correct as needed. Replace logic board if necessary.
Opener hums for 1-2
seconds no movement.
Manually open and close the door. Check for binding
or obstructions, such as a broken spring or door lock,
correct as needed. Replace motor if necessary.
16
Door coasts after it has
come to a complete stop.
Program travel to coasting position or have door
balanced by a trained door systems technician.
2 1-5 No movement, or sound. Replace logic board.
32
Unable to set the travel
or retain position.
Check travel module for proper assembly, replace if
necessary.
Diagnostic Chart
Your garage door opener is programmed with self-diagnostic capabilities. The UP and DOWN arrows on the garage
door opener will fl ash the diagnostic codes.