ARMY TM 5-6675-238-14
MARINE CORPS TM 08839A-14/1
Table 8-7. FAILURE/ACTION Indicator Number Definition - Continued
FAILURE/
ACTION number
Definition
Action
48
68
68
70
72
74
76
77
Action indication
Serial data bus error, or (digital)
d/DC error, or discrete loop
closer error
Buffer unit not properly connected
SPU digital/DC and digital/ syn-
chrodigital/resolver (gross magni-
tude) circuitry failure
SPU serial data bus decode and par-
ity circuitry failure. SPU discrete
test circuitry and lamp driver cir-
cuitry failure
Buffer unit verify function failure
Buffer unit load function, or input/
output failure
Normally a computer power status
failure. If it occurs at the end of
self-test, it represents a tape
reader time-out-counter failure
Requires operator to press all SPU switch-indicators for
self-test of these switch-indicators
Repeat step h of table 8-6. Check that the cables to the
SPU are connected as per figure 8-2. Special empha-
sis should be given to insure that cable W204 is
connected properly. If cables are connected properly,
replace A3. If still failure, replace A2, then A1
Check cabling. If cabling is good, replace A3. If still a
failure, replace Al. If still a failure, replace buffer
unit
Check SPU adjustments per paragraph 8-23. If adjusted
and still failure, replace A2, then A3, and then A1
Replace A3; if still failure, replace A1, then A2
Replace buffer unit; if still failure, replace A3, then A1
Replace buffer unit; if still failure, replace A1, then A3
Replace A3. If a failure still occurs, replace A1, then
buffer unit. If failure still occurs, perform tape reader
testing in accordance with table 8-8
NOTE
77 will always be present when not in self-test and the computer is not connected to
the SPU.
78
SPU digital/synchrodigital/ re-
Replace A2; if still failure, replace A1, then A3
solver angle and phase circuitry
failure
88
Normally a tape reader time-out-
Replace tape reader or perform tape reader testing and
counter failure. However, if it oc-
troubleshooting (table 8-8); if still a failure, replace
curs at end of self-test it repre-
Al, then A3. If it occurs at end of self-test, replace
sents a buffer power failure
buffer unit. If still a failure, replace A3, then A1
NOTE
After the required operation action has been performed (including switching power on and off where required), the
testing will continue.
8-63
