15
DIAGNOSTIC CHART
Symptom: One or both of the indicator lights on the IR Beams are not on
steadily.
• Inspect sensor wires for an electrical short (eg. staple in wire), correct wiring
polarity (black/white wires reversed), broken or disconnected wires, replace/attach
as needed.
• Disconnect all wires from the opener.
• Remove beams from brackets and shorten sensor wires to 30-60mm (1-2”) from
back each of sensor.
• Re-attach sending eye to opener using shortened wires. If sending eye indicator
light glows steadily, attach the receiving eye.
• Align beams. If the indicator lights glow, replace the wires for the beams. If the
sensor indicator lights do not light, replace the IR Beams.
Symptom: LED is not lit on door control.
• Check polarity of the wire connection to the opener.
• Inspect door control/wires for an electrical short (eg. staple in wire), replace as
needed.
• Disconnect wires at door control, touch wires together. If opener activates, replace
door control.
• If opener does not activate, disconnect door control wires from opener. Momentarily
short across red and white terminals with jumper wire. If opener 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: The RPM Sensor = Short travel 150-200mm (6-8").
• Unplug unit to reset. Try to operate opener, check diagnostic code.
• If it is still flashing 5 times and opener moves 150-200mm (6-8"), the APE
(Absolute Positioning Encoder) may need to be replaced, for details contact your
Chamberlain Merlin Professional Dealer.
Symptom: Door will not open or close
• Turn the power off and remove the Standby Power Unit (SPU) if installed.
• Turn power back on and plug the SPU back in. If opener fails to operate correctly
after resetting, contact your Chamberlain Merlin Professional Dealer
Symptom: Door fails to open all the way
• Turn the power off and remove the SPU if installed.
• Turn power back on and plug the SPU back in if installed. If opener fails to
operate correctly after resetting contact your Chamberlain Merlin Professional
Dealer.
Symptom: Opener will not open or close the door
• Contact your Chamberlain Merlin Professional Dealer.
• Report the number of flashes as the fault reference.
Possible APE error on
start up.
Possible RPM sensor
failure. Unplug to reset.
IR Beams slightly
misaligned
(dim or flashing LED).
Door control or
wire shorted.
IR Beams wire shorted or
black/white wire reversed.
IR Beams wire open
(broken or disconnected).
1 FLASH
2 FLASHES
3 FLASHES
4 FLASHES
5 FLASHES
6 FLASHES
OR
System Failure
Over current
7 FLASHES
10 to 15 FLASHES
