Thales 421, Эксплуатация и обслуживание, Страница: 168 / 256

LLZ 421
Fault Location Operation and Maintenance
ILS 420
6−26
Ed. 01.10 SOAC
6.5.3.4 Fault of the Local Control Panel (LCP)
The LCP is the focal point for communication which interfaces the local PC and the Remote Control to the transmitters and
monitors. The LCP evaluates directly the battery and the mains monitoring. The LCP consists of two boards: LC−CPU, LCI.
Step Fault A B C
1 Live lamp off LCP board: live lamp on LC−
CPU off. Liquid crystal display
screen is dark. Keys do not
function. Standstill of LCP−processor
or/and possibly no power sup-
ply. Measure at BP−Digital
supply 5V3 (and
−15 V) against GND. If
+5V3 is missing, check
fuse F4, which supplies
the DCC−5 for the LCP.
Replace F4 once if blown.
LCI: LCD
screen dark LCP board: live lamp on LC−
CPU on. Check −15 V voltage supply. If ok, replace LCI board
with LCD display.
2 Live lamp on At least one *.sit file is missing
or damaged in the LCP.
The RAM−check states a fault.
Call in ADRACS ’RC Manage-
ment’ submenu ’Control’ resp.
start ’MCS File Transfer’ tool,
⇒
select menu ’File Transfer’,
⇒
select function ’Show RAM
Directory’
All files available?
If necessary, restore the
floppy backup of the *.sit
files.
3 No commu-
nication be-
tween PC and
LCP. The LCP is ok. Indications
and controls directly at the
LCP are operating, but opera-
tion via PC is not possible. Interface cable between PC
and LCP is defective or con-
tacts are contaminated.
Configuration of PC not ok:
− Correct port used at PC?
− Is any other program
running at this port?
− PC User Program is
missing or damaged?
Check cable? Are the orig-
inal cable used:
Connector 9−pole, 0−Mo-
dem cable?
Check serial port at PC?
Check programs.
Reload PC User Program,
if necessary.
4 No interroga-
tions to monitor
or transmitter. Audio_ON LED (lower of two
LED) at the LG−M or LG−A
does not sparkle regularly
(This LED indicates received
interrogations from LCP to
monitor or transmitter). Transmitter and monitor are
switched on?
Check, if 64−pole flat ribbon
cables from BP−Digital, con-
nector J13 to LCP are defec-
tive or have come loose.
The LCP interrogates only
processors which are
switched on.
Replace or fix cables.
cont. Both LG−M and both LG−A
are not interrogated.
At least one LG−M and
LG−A communicates with the
LCP.
The LCP is presumably defec-
tive.
The fault can be located possi-
bly in the LCP or in the trans-
mitter or monitor subassem-
blies (LG−M or LG−A)
Replace the LCP comple-
tely.
Replace first LG−M or
LG−A, than LCP (or LC−
CPU) if replacement of
LG−M/LG−A was not
successful.
cont. No interroga-
tions to monitor
or transmitter. Audio_ON LED (lower of two
LED) at the LG−M or LG−A
does not sparkle regularly
(This LED indicates received
interrogations from LCP to
monitor or transmitter). Transmitter and monitor are
switched on?
Check, if 64−pole flat ribbon
cables from BP−Digital, con-
nector J13 to LCP are defec-
tive or have come loose.
The LCP interrogates only
processors which are
switched on.
Replace or fix cables.