ARMY TM 5-6675-308-34
MARINE CORPS TM 08837A-34/2
Table 4-14.1. IMU Testing, Alignment, and Troubleshooting Using Tape Reader, Part No. 877406-2 --
Continued
Malfunction
indication/corrective action
Test procedure
Normal indication
WHEN DONE TYPE:
RDY
ALIGNMENT HALTED:
Ensure IMU is oriented to 45 10
degrees to any cardinal heading and
azimuth is correct. Type RDY.
TTY will request a new measure-
ment of the last horizontal angle
followed by azimuth entry
TTY prints out:
TYPE ONE OF: ACC REP, BYP
ALIGNMENT HALTED:
Type REP and repeat theodolite
test. If test fails a second time,
replace the porro prism assembly
TTY prints out:
THEODOLITE READING IN-
NOTE
CONSISTANT
A complete table of calibration pa-
TYPE ONE OF: REP, BYP
rameters, including the cal data
checksum, will print during subtest
Before using the theodolite readings
10. A failure table will print after
to calculate the porro prism cali-
test 10 results, OK means the param-
bration constants, several feasabil-
eter was within tolerance; OOC
ity checks will be run on the read-
means the parameter was out of tol-
ings, If one or more readings were
erance but has been recalibrated;
in error, these checks will detect
FAIL means the parameter was out
an inconsistancy and give the op-
of tolerance and must be corrected
erator the option of repeating the
at the depot level.
readings or bypassing the test. If
an inconsistency is detected for
three consecutive sets of readings,
the system will assume that PADS
is in error and will print out an
IMU failure. Return IMU to depot
if any lines 1020 thru 1025 indi-
cate a failure. If only line 101 or
102 indicates a failure, replace the
porro prism assembly.
Return IMU to depot if following
At end of test, TTY prints out:
test 9, TTY prints out:
ALIGNMENT COMPLETED
NEED DEPOT CAL
000000 000000
2s. Press EXECUTE switch-indica- EXECUTE switch-indicator goes off
tor to off
2t. Sequentially press PADS ON/ PADS ON/OFF switch-indicator
OFF switch-indicator and EN-
goes off
TER switch
System shuts down
4-90.10
Change 5
Previous Page
