2. Ensure IFF XPDR is selected at Reversionary
3. On PNF CDU TUNE page, ensure EXT CTL
is displayed at L5 Line Select Key.
4. On APX 119 control panel, set Master selector
switch to TA/RA.
5. Ensure both MODE 4 switches are in OUT
Most failures of TCAS test with APX-119
transponder are caused by insuficient
warm-up time between selection from ATC1
to IFF XPDR.
6. Push MODE 3/A switch to test position and
a. "M3 PASS" in display window on APX-119
b. PFD displays red and green VSI advisory
bands on vertical scale. Message TCAS
TEST (white) shows below vertical speed
c. Observe displays to see TFC symbol is
highlighted by cyan (blue) background;
press adjacent Line Select Key on both
PFDs and MFD.
d. TCAS test pattern that is displayed
includes four types of trafic symbols
message TCAS TEST (white); and TCAS
FAIL (red if test fails).
e. Audio -- Ensure aural message, "TCAS
SYSTEM TEST OKAY" is heard.
Test 2 (Full time display)
When not selected for light operations,
APX-119 must be kept in STBY mode.
Both transponders/TCAS must be tested be-
fore irst light of day. For subsequent thru
lights, only transponder/TCAS intended for
use, for that light, must be tested.
Change 1 P-15