TM 11-5805-715-34/EE119-DB-MMI-010/E154 CV3478/TO 31W2-2TTC39-12
Section III. TROUBLESHOOTING
3-6. Direct Support Operational Check
3-4. General
This section provides the fault isolation and de-
Upon completion of repairs within the system, per-
tailed troubleshooting procedures required to
form appropriate tests to verify the corrective
identify and correct a malfunction. The trouble-
actions. The tests should be localized around the
shooting procedures are divided into two
faulted area (for example, a faulty channel).
categories. These are: (1) verification of a fault
Coordinate the transmit and receive level
indicated by organizational maintenance, and (2)
adjustments outlined in TM 11-5805-715-12.
subsequent troubleshooting procedures which may
be either organizational or direct support level.
Verification of organizational maintenance action is
3-7. Connector Plate Assembly
required to determine if the malfunction is correct-
Maintenance
able using organizational level procedures and, if
the problem has not been found, the fault requires
The connector plate assembly provides the inter-
direct support troubleshooting procedures to locate
face connections between the individual printed
it. Perform the following procedures to verify the
circuit cards within the unit. It also provides input/
organizational maintenance actions:
output signal connections which interface the unit
a.
Review organizational maintenance
with the rear panel and power supply. The 76-pin
records to determine which circuit card assemblies
card connectors are mounted vertically with the
have been replaced.
pins feeding through holes to the wire wrap side.
b. Review the reported malfunction with the
The 70-pin signal and power connectors are
cognizant organizational personnel. Ascertain the
mounted
horizontally.
All
connector
troubleshooting results and actions taken.
interconnections are accomplished using wire wrap
c. Based upon the results of a. and b.
terminations. Connector plate failures will result in
above, per- form such corrective maintenance at
the same type of failure indications as failed cards,
direct support as required.
but will not be corrected by card replacement. The
majority of connector plate failures can be isolated
and corrected by direct support personnel using
3-5. Voltage and Resistance
visual inspection, continuity checks, and wire lists.
Measurements
a. Connector Plate Assembly Removal.
(1) Remove all plug-in circuit cards from
Voltage, resistance, and continuity measurements
the card assembly nest. Refer to circuit
are made by direct support maintenance for
card removal outlined in TM 11-5805-
troubleshooting faults which cannot be resolved or
715-12.
repaired by organizational level maintenance.
(2) Remove power supply by performing
Normally such faults are traceable to wiring or
step a (1) through (6) of paragraph 3-11.
chassis- mounted components. Use the wire run
(3) Using a flathead screwdriver, release
lists (tables 3-2 through 3-7), and foldout diagrams
the two jackscrews securing P3(J7) to the
FO-1, FO-3, FO-4, FO-5, and FO-6 to support this
connector plate assembly. Remove
troubleshooting. Channel assignment input/output
power supply.
breakout connections for the J-box U-185/J-1077
(4) Remove rear panel by performing
pairs are shown in table 3-4.
step a of paragraph 3-10. Place rear
panel to the side.
(5) Using a flathead screwdriver, remove
16 screws securing the connector plate
assembly to the frame and remove the
connector plate assembly from the
equipment case.
(6) Refer to paragraph 3-8 to perform
maintenance on the connector plate
assembly.
3-2
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