Part Number: 72-0075-02-B.doc Page 2
MCU Status LED Codes
ERROR LED STATUS LEDs Description
OFF Random Cycling The Link 150 is powering up. Initialization to follow.
OFF 5 The Link 150 is initializing. Code number will change when finished.
OFF 1, 2, 3, or 4 MCU identification number.
ON 1, 2, 3, 4, 5 MCU has not been configured for switch interface type. Assign a switch type to the MCU.
ON 4, 5 The switch type selected is not supported by this MCU. Verify that the switch type selected
is correct. If the type is incorrect, repeat the steps to select a new switch type.
ON 1, 3 A Base Station has reported an internal problem. Replace the Base Station. The error
display refers to the Base Station LED that is flashing red. If more than one Base Station
LED is flashing red, it refers to the lowest numbered Base Station.
ON 2, 3 No communication with one or more Base Stations on this MCU. The error display refers to
the LED that is flashing red. If more than one Base Station LED is flashing red, it refers to
the lowest numbered Base Station.
ON 1, 2, 3 Internal communication problem with the MCU. Power cycle the MCU. If the problem
persists, replace the MCU.
ON 4 IPC Problem. Check IPC cabling by disconnecting and reconnecting the IPC cable joining
the MCUs. Connect the Male RJ-21 connector from the appropriate demarcation block to
the designated RJ-21 connector (Aor B) on each MCU. If error still occurs, replace the IPC
cable. Replace the MCU if the problem continues.
ON 1, 4 The operator is trying to register a handset on an MCU with no phone lines. Return the
mode switch to the NORMAL position.
ON 2, 4 The MCU was powered on with the mode switch in the wrong position. Turn off the MCU,
move the mode switch to the NORMAL position and turn back on.
ON 3, 4 Configurations on a multi-MCU installation do not match in each of the units. Most likely
to occur when an MCU was just added to the system. Erase the configuration in the MCU
with incorrect configuration definitions (probably the MCU that was just added).
Note:
Do not erase the configurations in all the MCUs. In multiple MCU installations the
handset registration information is shared among the MCUs. This allows you to replace an
MCU without re-registering all the handsets.
ON 1, 3, 4 REGISTER or ADMIN mode selected on more than one MCU at the same time. Check
the MCUs and take one of them out of REGISTER or ADMIN mode.
OR
The operator is trying to place an admin call on MCU #1 with no handset registered to
MCU #1, Line 2. Return the mode switch to the NORMAL position.
ON 2, 3, 4 The MCU was powered on with the mode switch in the wrong position. Turn off the unit,
move the mode switch to the NORMAL position and turn back on.
ON 1, 2, 3, 4 Internal problem with the MCU. Contact SpectraLink Customer Service for technical
support.
ON 1, 5 Possible Base Station failure. A Base Station that had previously been heard by another
Base Station can no longer be heard. Turn off the MCU, move the mode switch to the
NORMAL position and turn back on. Check to see if system was powered on with mode
switch in the wrong position. If not, contact SpectraLink Customer Service.
