ARMY TM 9-1240-379-34
MARINE CORPS TM 04332A-34
Table 2-1. TROUBLESHOOTING (cont)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
5. POOR VISION THROUGH INFRARED BODY ASSEMBLY.
Step 1. Check for proper alinement of reticle.
Adjust diopter length.
Step 2. Check for dirt or fingerprints on all exposed optical surfaces.
Clean optics in accordance with TM 9-254.
Step 3. Check for condensation; if moisture is present, check for defective sealing
or a defective valve core and purging valve stem using a soapy solution.
Replace valve core (page 2-27) or purging valve stem (page
a.
2-27), as necessary.
b.
Purge and charge in accordance with TM 750-116.
c.
If sealing is defective, replace infrared body assembly (page
2-8).
ELBOW ASSEMBLY
6. POOR OR NO ILLUMINATION OF NIGHT RETICLE.
Step 1.
Check that RETICLE control knob is properly adjusted.
Step 2. Check for damaged or defective incandescent lamp.
Replace incandescent lamp (page 2-39), as necessary.
Step 3. With objective lens covered to simulate darkness, turn shutter assembly
switch to 3 V ON position and operate TUBE control knob.
a.
If image intensifier lights, notify next higher level of
maintenance to replace RETICLE control knob.
b.
If image intensifier does not reflect a green grain image, notify
next higher level of maintenance to replace regulator
assembly.
c.
Replace elbow assembly (page 2-8), if required.
2-5
