Harris Constellation - Page 145

Harris Corporation Constellation™
Troubleshooting Guidelines 11-9
TROUBLESHOOTING
GUIDELINES
FAN ALARM (A1, A2, B1,
B2)
Fan is not operating:
a blown fuse
defective part
If Keypad displays Fan Alarm:
but red LED on Fan is not
lighted, try replacing fuse. If
Fan still does not operate, the
cause may be a defective Fan.
If Keypad does not display Fan
Alarm:
the cause may be a defective
Transmitter.
FEC LOCK
FEC LOCK A, B
Reed-Solomon FEC decoding is out
of lock in the Modem.
Fault may be receive path, far-
end Transmitter, or far-end
Modem.
FUSE ALARM Blown fuse in Fuse Panel A. Replace the blown fuse.
HLM-1, 2 ABSENT HLM card unplugged or not installed
per configuration.
Defective HLM.
Is the HLM is plugged in?
If yes, replace the defective
HLM. See Chapter 12.
INPUT LOS (DS3)
INPUT LOS (Tributary
A1-A28, B1-B16)
No signal present at DS3 input.
No signal present at DS1 input.
Check input.
LOCAL CLOCK On the 3xDS3 unit, one of the three
onboard oscillator has failed.
Replace High Level Mux.
LOCK HLM 1, 2 HLM 1 or 2 is locked on line. From the Keypad:
CONTROL > LOCK/IF LPBK >
LOCK HLM > CLR
LOCK DEMOD / RX A1, A2
LOCK DEMOD / RX B1, B2
Traffic is locked onto Receiver Assy
An.
Traffic is locked onto Receiver Assy
Bn.
From the Keypad:
CONTROL > LOCK/IF LPBK >
LOCK DMOD/RX > CLR
LOCK MOD / TX A1, A2
LOCK MOD / TX B1, B2
Traffic is locked onto Transmitter
Assembly An.
Traffic is locked onto Transmitter
Assembly Bn.
From the Keypad:
CONTROL > LOCK/IF LPBK >
LOCK MOD/TX > CLR
LOSS OF -12V Transmitter has failed.
Trouble in the Power Supply.
Replace the Transmitter. See
Chapter 12.
M12-1...M12-8 ABSENT M12 Unit is unplugged.
The M12 slot is different from the
configuration when the system was
first turned on.
Defective M12 Unit.
Is the M12 Unit plugged in?
Check the configuration with the
Keypad.
Replace the defective M12 Unit.
See Chapter 12.
M12-1...M12-8 RX CLK M12-1...M12-8 Unit is not receiving
CLK from HLM.
Probable cause is a faulty HLM.
M12-1...M12-8 TX CLK M12 Unit is not receiving TX CLK
from HLM.
Probable cause is a faulty HLM.
Message Explanation
Course of Action/Possible
Causes