TM 55-1520-240-T
S Y M P T O M
T A S K
EDGE LIT PANEL DOES NOT LIGHT OR VARY
18-3.4
CDU MAL LAMP AND ALL LED SEGMENTS ARE
18-3.5
NOT ILLUMINATED
CDU DISPLAY NOT GO ALL
18-3.6
CHAPTER 18
INSTALLED AVIONIC SYSTEMS TROUBLESHOOTING
CHAPTER OVERVIEW
FAILURE SYMPTOM LIST (Continued)
DOPPLER/GPS NAVIGATION SYSTEM (DGNS)
S Y M P T O M
T A S K
GPS ALERT INDICATOR DOES NOT ILLUMINATE
18-3.7
PRESENT POSITION NOT DISPLAYED ON CDU
18-3.8
CDU DOES NOT DISPLAY DOWNLOAD WAYPTS
18-3.9
DURING WAYPOINT LOADING
S Y M P T O M
INDICATIONS ON THE FOUR-LINE DISPLAY
AND HSI ARE NOT THE SAME
T A S K
18.3.10
GPS DOES NOT ZEROIZE
18-3.11
GPS HAVEQUICK TIMING NOT WORKING
18-3.12
Change 19 18-4.1
