TM 55-1520-240-T
16-212 Change 24
16-5.6 LANDING GEAR SWITCH STATUS, READY TO FIRE, OR LANDING GEAR BYPASS LIGHTS DO NOT LIGHT DURING PRESS TO TEST (Continued)
16-5.6
DO ANY OF THE
THREE LIGHTS
ILLUMINATE DURING
PRESS-TO-TEST?
DISCONNECT PLUG
147P4 FROM
REMOTE BYPASS
SWITCH PANEL. IS
28 VDC PRESENT ON
PIN B?
IS GROUND
PRESENT ON
CONNECTOR 147P4
PIN A?
LOCATE AND
REPAIR FAULT ON
REMOTE BYPASS
SWITCH PANEL.
DOES LDG GEAR
BYPASS LIGHT
ILLUMINATE DURING
PRESS-TO-TEST?
OPEN EAPS/MEAPS CB
PANEL. CHECK FOR CON-
TINUITY FROM DCDU CB
CIRCUIT SIDE TO PLUG
147P4 PIN B. IS CONTINUITY
PRESENT?
IS 28VDC PRESENT
ON BUS SIDE OF
DCDU CIRCUIT
BREAKER?
LOCATE AND REPAIR
FAULT IN WIRE W668-
6D289B20N.
REPAIR FAULTY WIRING
BETWEEN DCDU AND
CONNECTOR 147P4 PIN B.
REPAIR/REPLACE
FAULTY WIRING/
COMPONENT ON LDG
GEAR REMOTE BYPASS
PANEL.
NO
REPLACE LAMP IN
READY TO FIRE LIGHT
AND PRESS TO TEST.
DOES LAMP
ILLUMINATE?
DOES LDG GEAR
REMOTE BYPASS
SWITCH STATUS
LIGHT ILLUMINATE
DURING PRESS-TO-
TEST?
REMOVE AND
REPLACE FAULTY
DCDU CIRCUIT
BREAKER.
TROUBLESHOOT NO. 1
DC BUS. (TASK 9-1.4)
REPLACE LAMP AND
PRESS TO TEST. DOES
LAMP ILLUMINATE?
REPLACE LAMP AND
PRESS TO TEST. DOES
LAMP ILLUMINATE?
LOCATE AND REPAIR
FAULT IN REMOTE
BYPASS SWITCH PANEL.
YES
YES
NO
NO
FAULT CORRECTED.
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
YES
NO
NO
YES
REPAIR/REPLACE FAULTY
WIRING/COMPONENT ON
LDG GEAR REMOTE BYPASS
PANEL.
FAULT CORRECTED.
END OF TASK
