UTMC OTU/MOVA Handbook
667/HB/31601/000
Page 113
Issue 5
8.4 TABLE FOR EQUIPMENT FAILURES
Symptom
Possible Diagnosis
Action to Check Diagnosis
(a) Unit not operating
Software watchdog has
triggered
Check the state of the Watchdog LED (see section 5.3 which starts on page
35), if lit power down and power up the unit to cause a reset. If Watchdog LED
lights again, replace the Processor card. If the Watchdog LED lights again,
replace the unit.
Processor card failed
Check the state of the System LED (see section 5.3 which starts on page 35), it
should be flashing. If it is either permanently on or off power down and power
up the unit to cause a reset. If the error condition persists replace the
Processor card. If the System LED stops flashing again, replace the unit.
(b) IO card faults
Digital input failed
Monitor the relevant input(s) using the din command. If the indications are
incorrect, replace the relevant IO cable and card. If the indications are correct,
replace the Processor card. If the fault persists, replace the unit.
Digital output failed
Monitor the relevant output(s) using the dout command. If the output does not
function as displayed, replace the relevant IO cable and card. If the fault
persists, replace the unit.
Unit not able to read the
inputs and outputs on
certain groups of ports
belonging to an IO card
Check that the address switches of suspected cards are set correctly (see
section 4.2.1 on page 25). If OK, replace that IO card. If not OK, set the
switches to the correct setting.
(c) Handset port not
operating
Terminal configured
wrong
Check that the terminal is set correctly, at 57600 baud, with 1 start bit, 7 data
bits, 1 stop bit and even parity.
Wrong type of terminal If the terminal can not be set to act as a dumb terminal, at 57600 baud, with 1
start bit, 7 data bits, 1 stop bit and even parity, then replace the terminal. The
terminal must use the RS232 DTR/DSR control lines.
Handset port failed
Check the terminal is set correctly and that it’s interconnection cable is not
damaged. If the handset port still does not work, replace the Processor card.