TM 11-5821-333-30
6-20. OPERATIONAL CHECK. Continued
ACTION
RESPONSE
Step 1. DC POWER TEST
a. Connect equipment as shown in figure 6-39.
a. No response.
Set all switches as listed,
b. Set test adapter DC switch to ON.
b. DC switch stays ON. If DC trips OFF, go to
chart 2.
DC lamp is lit. If not, go to chart 3.
c. Set DMM to read voltage. Connect DMM
probes to TP22 (+) and TP24 (-).
c. DMM reading is 6.25 to 7.25 V dc. If not, re-
place lamp test CCA. If still bad, use trouble-
shooting schematic 1.
Step 2. TEST LAMPS TEST
a. Connect DMM probes to TP21(+) and
TP24(-).
b. Set test adapter LAMP TEST switch (S16)
to ON.
a. DMM reading is 4,5 to 5,5 V dc. If not, replace
voltage regulator U1 and capacitor C2. If still
bad, use troubleshooting schematics 1 and 2.
b. All test lamps light, If not, then do the follow-
ing:
IF
No test lamps lit.
Test lamps flicker
on and off.
One test lamp
fails to light.
Only test lamps 1
and 4 light.
Only test lamps 2,
3, and 5 through
10 light.
THEN
Replace LAMP TEST
switch (S16).
Replace LAMP TEST
switch (S16).
Go to chart 4.
Replace LAMP TEST
switch (S16).
Replace LAMP TEST
switch (S16).
NOTE
If problem not corrected, use
troubleshooting schematic 2.
6-164
