M2/M3 BFV: FIRE CONTROL SYSTEM - OD1608 - LESSON 2/TASK 4
component has been located and repaired or replaced, test 2731 should
be repeated to verify a NO FAULTS FOUND condition.
(1) Testing Wiring Harness 2W201. The first suspect component
is wiring harness 2W201.
To see if wiring harness 2W201 is good,
four tests are run. If any of the four tests described in paragraphs
2c(1) (a) through (d) below indicate that wiring harness 2W201 is not
good, replace the wiring harness following the procedures outlined in
TM 9-2350-252-20-2-3, page 24-31.
Then repeat test 2731 to verify
that the problem has been solved.
(a) Perform test 2390 between plug 2W201P2 and jack 2W201J1
at the diagnostic panel jack 2.
(b) If wiring harness tests good during test 2390 between
plug 2W210P2 and jack 2W201J1, perform test 2391 on jack 2W201J1 at
the diagnostic panel jack J2.
(c) Perform test 2390 between plug 2W201P1 and jack 2W201J1
at diagnostic panel jack 2.
(d) Perform test 2390 between plugs 2W201P1 and 2W201P2.
(e) If no faults are found in wiring harness 2W201 during the
four tests described in paragraphs 2c(1) (a) through (d), the problem
could be a loose connection.
Therefore, the next step is to check
various connections for tightness.
(2) Checking Connections for Tightness.
Problems in the ISU
mirrors, the ISU gun reticle, and the TOW mirror can be caused by
loose connections.
The following inspections should be made for
loose connections.
Whenever a loose connection is found, it should
be tightened.
First, turn the MASTER POWER switch and the TURRET
POWER switch OFF. Then perform these connections checks.
(a) Check connections 2Wl03P1 to
2A1044J2
and
2W103P5
to
2A1044J1 (refer to figure 60 on page 91).
(b) Inspect connection 2W101P5 at 2W103J1 (refer to figure 61
on page 92).
103