Permanent Display of Terrain Data on CAPT ND

TASK 34-48-00-810-834-A
Permanent Display of Terrain Data on CAPT ND

1. Possible Causes

GPWC [1WZ]
P/BSW-TERR ON ND,CAPT [30WZ1]
wiring of the TERRAIN POP-UP CAPT discrete between the GPWC (1WZ) and the TERR ON ND, CAPT pushbutton switch (30WZ1)

2. Job Set-up Information
A. Referenced Information

3. Fault Confirmation
Subtask 34-48-00-740-104-A

A. Test
(1) Do the BITE test of the Enhanced GPWS AMM 34-48-00-740-002.

4. Fault Isolation
Subtask 34-48-00-810-110-A

A. If the BITE test gives the maintenance message:
CAPT TERR ON ND PB SW (30WZ1)/GPWC (1WZ)

on the TERR ON ND PNL (403VU), make sure that the TERR ON ND, CAPT pushbutton switch (30WZ1) is not pushed (the ON legend is off)
do a check for ground at pin AA/1A of the GPWC ASM 344802.

(1) If there is no ground:

(2) If there is ground:

(a) If the fault continues:

do a check and repair the wiring of the TERRAIN POP-UP CAPT discrete between the GPWC (1WZ) and the TERR ON ND, CAPT pushbutton switch (30WZ1): for pin AA/1A of the GPWC ASM 344802.

Subtask 34-48-00-740-105-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:17 UTC