NAVELEX EE 181-AA-OMI-120/E121 C-7359-60-1
Table 5-1. Troubleshooting Procedures - Continued
code plug so that dot or notched
comer on plug lines up with dot
on PC board. Carefully push
plug into socket. Replace cover
and secure with screws. Posi-
tion new Transmitter over stand-
offs in CU and insert screws.
Tighten screws to secure Trans-
mitter. Connect wires to TB6
and TB7 in CU.
e. Bad Data Receiver.
To gain access to Data Receiver for
troubleshooting, open Monitor Cabi-
net, and turn off switch S1 on power
supply. Release swingout rack. Re-
move screws that secure status moni-
tor module to rack and remove status
monitor module through front of
rack. Loosen captive screws and
remove Data Receiver from bottom
of module. Remove Receiver cover
and put tape over interconnecting
subassembly. Plug Data Receiver into
status monitor module and tem-
porarily secure with string or tape.
Ensure that test points on bottom
edge of PC boards are not covered.
Replace status monitor module
in swingout rack and secure with
screws. Turn on switch S1 on
power supply. Wait one or two
minutes for system to stabilize;
then push RESYNC button in
a. Set multimeter to dc volts and
connect positive meter lead to
Data Receiver PC board A4-TP4,
yellow, and negative meter lead
to A4-TP3, orange. Meter should
indicate 20 ±1 vdc.
b. Connect positive meter lead to
A4-TP2, red, and negative meter
lead to A4-TP3, orange. Meter
should indicate 6.8 ±0.4 vdc.