Loss of the RA1 and RA2 Input to the GPWC

TASK 34-48-00-810-854-A
Loss of the RA1 and RA2 Input to the GPWC

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 34-42-00-740-002	BITE Test of the Radio Altimeter
AMM 34-42-33-000-001	Removal of the Radio Altimeter Transceiver
AMM 34-42-33-400-001	Installation of the Radio Altimeter Transceiver
AMM 34-48-00-740-002	BITE Test of the GPWS
ASM 344801
ASM 344802
AMM 34-48-34-000-001	Removal of the GPWC
AMM 34-48-34-400-001	Installation of the GPWC

3. Fault Confirmation
Subtask 34-48-00-740-116-A ** ON A/C NOT FOR ALL

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

4. Fault Isolation
Subtask 34-48-00-810-119-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance messages RA1(2SA1)/GPWC(1WZ) and RA2(2SA2)/GPWC(1WZ):

(1) If the test gives a maintenance message:

(2) If the test does not give a maintenance message:

(a) If the fault continues:

replace the XCVR-RA, 1 [2SA1] and the XCVR-RA, 2 [2SA2] AMM 34-42-33-000-001 and AMM 34-42-33-400-001.

1 If the fault continues:

do a check and repair the wiring from the GPWC (1WZ) to the radio altimeter transceiver 1 (2SA1): from pins AB/13A, 13B to pins AB/2G, 3G ASM 344801.
do a check and repair the wiring from the GPWC (1WZ) to the radio altimeter transceiver 2 (2SA2): from pins AA/8C, 8D to pins AB/2G, 3G ASM 344802.

Subtask 34-48-00-740-117-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:18 UTC