Chamberlain 3585CS 3/4HP 1 FLASH, FLASHES, FLASHES, FLASHES, FLASHES, FLASHES, Diagnostic Chart, Logic Board, wire shorted, disconnected), not glow steady, Door control or

Bell Wire
	Diagnostics
	Located On
	Motor Unit
	"Learn"
	Button
	LED or
	Diagnostic
Safety Reversing Sensor	LED
Safety Reversing Sensor

Diagnostic Chart

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.

1 FLASH		Symptom: One or both of the Indicator lights on the safety sensors do
Safety reversing sensors		not glow steady.
		• Inspect sensor wires for a short (staple in wire), correct wiring polarity
wire open (broken or
		(black/white wires reversed), broken or disconnected wires, replace/attach
disconnected).		as needed.
	OR	• Disconnect all wires from back of motor unit.
2	FLASHES	• Remove sensors from brackets and shorten sensor wires to 1-2 ft. (30-60 cm)
		from back each of sensor.

Safety reversing sensors		• Reattach sending eye to motor unit using shortened wires. If sending eye
		indicator light glows steadily, attach the receiving eye.
wire shorted or black/
		• Align sensors, if the indicator lights glow replace the wires for the sensors. If
white wire reversed.
		the sensor indicator lights do not light, replace the safety sensors.

3	FLASHES	Symptom: LED is not lit on door control.
Door control or		• Inspect door control/wires for a short (staple in wire), replace as needed.
Door control or		• Disconnect wires at door control, touch wires together. If motor unit activates,
wire shorted.
wire shorted.		replace door control.
		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.

4	FLASHES	Symptom: Sending indicator light glows steadily, receiving indicator light
		is dim or flashing.
Safety reversing sensors
		• Realign receiving eye sensor, clean lens and secure brackets.
slightly misaligned
		• Verify door track is firmly secured to wall and does not move.
(dim or flashing LED).

5	FLASHES	Symptom: Motor has over heated; the motor unit does not operate or
		trolley is stuck on stop bolt = Motor unit hums briefly; RPM Sensor =

Motor overheated or		Short travel 6-8" (15-20 cm).
possible RPM sensor		• Unplug unit to reset. Try to operate motor unit, check diagnostic code.
failure. Unplug to reset.		• If it is still flashing 5 times and motor unit moves 6-8" (15-20 cm), replace

		RPM sensor.
		• If motor unit doesn’t operate, motor unit is overheated. Wait 30 minutes and
		retry. If motor unit still will not operate replace logic board.

6	FLASHES	Symptom: Motor unit doesn’t operate.
Motor Circuit Failure.		• Replace logic board because motor rarely fails.
Motor Circuit Failure.
Replace Receiver
Logic Board.
Logic Board.		31
		31