Diagnostic Chart - Craftsman 139.18458DM Owner's Manual

Bell Wire
Safety Reversing Sensor

Diagnostic Chart

1 FLASH
Safety reversing sensors
wire open (broken or
disconnected).
OR
2 FLASHES
Safety reversing sensors wire
shorted or black/white wire
reversed.
3 FLASHES
Door control or wire
shorted.
4 FLASHES
Safety reversing sensors
slightly misaligned
(dim or flashing LED).
5 FLASHES
Motor RPM is not
recognized.
Diagnostics
Located On
Motor Unit
LED or
Diagnostic
LED
"Learn"
Button
Symptom: One or both of the Indicator lights on the safety reversing sensors do not glow
steady.
• Inspect sensor wires for a short (staple in wire), correct wiring polarity (black/white wires
reversed), broken or disconnected wires, replace/attach as needed.
• Disconnect all wires from back of motor unit.
• Remove sensors from brackets and shorten sensor wires to 1-2 ft (30-60 cm) from back each
of sensor.
• Reattach sending eye to motor unit using shortened wires. If sending eye indicator light glows
steadily, attach the receiving eye.
• Align sensors, if the indicator lights glow replace the wires for the sensors. If the sensor
indicator lights do not light, replace the safety reversing sensors.
Symptom: The door doesn't activate from the door control.
• Inspect door control/wires for a short (staple in wire), replace as needed.
• Disconnect wires at door control, touch wires together. If motor unit activates, replace door
control.
• If motor unit does not activate, disconnect door control wires from motor unit. Momentarily
short across red and white terminals with jumper wire. If motor unit activates, replace door
control wires.
Symptom: Sending indicator light glows steadily, receiving indicator light is dim or flashing.
• Realign receiving eye sensor, clean lens and secure brackets.
Symptom: Door travels 2-3 inches and stops.
• Reprogram limits and forces. See Adjustment section.
• If the motor unit continues to travel 2-3 inches, check the travel module connection or replace
the travel module.
Symptom: No movement, motor runs 2-3 seconds.
• Reconnect the emergency release.
• Motor may need to be replaced.
Installed
Safety Reversing
Sensor
Your garage door opener is programmed with self-diagnostic capabilities.
The "Learn" button/diagnostic LED will flash a number of times then
pause signifying it has found a potential issue. Consult Diagnostic Chart
below.
34