TM 11-6130-392-34
a. Check Panel Meter.
k. With positive lead of multimeter, measure
voltage at pins 2, 3, 4, 13, 22 and 26 of A12 timing
(1) If meter shows current reading; go to step
b.
circuit assembly.
(2) If no current reading on meter; go to step e.
(1) If the meter reading is less than 1 volt for
each pin, set POWER switch to OFF and replace
A12 (Section IV, para. 3-16).
c. Set multimeter to 10 VDC scale. Connect nega-
(2) If the meter reading is 1 volt or more for
tive meter lead to negative () terminal of filter
any pin; discontinue testing, send battery charger
capacitor C1 (fig. 3-3). Connect positive (+) lead to
to next higher maintenance level. Go to section V.
l. Set POWER switch to OFF. Remove all display
modules. Be sure to remember which module goes
(1) If the meter reading is 7.0 volts or more; go
to step d.
into each socket. Refer to section IV, paragraph
3-17 for disassembly instructions.
(2) If the meter reading is less than 7.0 volts;
discontinue testing, send battery charger to next
higher maintenance level.
d. Remove positive lead of multimeter from
each pin of each display module socket and the ap-
A12-TP2 and connect to S3-TP1 (fig. 3-3).
(1) If meter reading is less than 7.0 volts; dis-
3-7.
c o n t i n u e testing, s e n d b a t t e r y c h a r g e r t o n e x t
higher maintenance level.
step o.
(2) If meter reading is 7.0 volts or more; set
POWER to OFF, replace A12 (Section IV, para 3-
(2) If continuity is not good for all of the pins;
16), go to section V.
discontinue testing, send battery charger to next
higher maintenance level.
check continuity with multimeter.
o. Insert display modules into their original
sockets.
(1) If F6 is good; go to step f.
(2) If F6 is faulty; go to step m .
p. Remove and interchange any two of the dis-
play modules.
supply assembly (fig. 3-2) on extender board. Insert
q. Set POWER switch ON. Press START TIME
F6 fuse and screw-on cap.
switch.
g. Set POWER to ON. Set multimeter to 50 VAC
(1) If display reads exactly the same as in step
scale. Measure A11 (fig. 3-4) AC volts between pins
a; go to step r.
A11-22 and A11-23 on extender board.
(2) If display does not read exactly the same as
in step a; set POWER switch to OFF. Replace all
(1) If meter reading is 7.0 volts or more; go to
step h.
display modules and reassemble display circuit as-
(2) If meter reading is less than 7.0 volts; dis-
continue testing, send battery charger to next high-
r. Set multimeter to 10 VDC scale. Connect nega-
er maintenance level.
tive lead to negative () lead of C1 (fig. 3-3). With
h. Set multimeter to 10 VDC scale. Connect mul-
positive (+) lead of multimeter, measure voltages at
timeter negative lead to negative () lead of C1 (fig.
pins 1, 27, and 28 of A12 timing circuit assembly (fig.
3-3). Connect the positive lead to A11-TP3 (fig.
(1) If meter reading is 9.0 volts or greater for
(1) If meter reading is 7.0 volts or more; go to
each pin measured, go to steps.
step i.
(2) If meter reading is less than 9.0 volts for
any pin measured, discontinue testing, send battery
(2) If meter reading is less than 7.0 volts; set
POWER to OFF, and replace A11 (Section IV, para
charger to next higher maintenance level.
s. With positive lead of multimeter, measure
voltage at pins 2, 3, 4, 13, 22 and 26 of A12 timing
i. Set POWER switch to OFF. Remove positive
circuit assembly.
the extender board and return All into its original
(1) If the meter reading is less than 1 volt for
each pin, set POWER switch to OFF and replace
j. Set POWER switch ON. Connect positive lead
(2) If the meter reading is 1 volt or more for
of multimeter to A12 (fig. 3-6) by using pin 41 on ex-
any pin; discontinue testing, send battery charger
to next higher maintenance level.
tender board.
Test 6. 10 Volt Power Supply Test.
(1) If meter reading is 7.0 volts or more; go to
3-12