Failure of the Waveguide Switch (System 1)

TASK 34-41-00-810-818-A
Failure of the Waveguide Switch (System 1)

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 34-41-00-740-002	BITE Test of the Weather Radar
ASM 344101
AMM 34-41-12-000-001	Removal of the Weather Radar Control Unit
AMM 34-41-12-400-001	Installation of the Weather Radar Control Unit
AMM 34-41-33-000-004	Removal of the Weather Radar Transceiver
AMM 34-41-33-400-003	Installation of the Weather Radar Transceiver
AMM 34-41-37-000-001	Removal of the Weather Radar Transceiver Mounting Tray
AMM 34-41-37-400-001	Installation of the Weather Radar Transceiver Mounting Tray

3. Fault Confirmation
Subtask 34-41-00-740-082-A

A. Test
(1) Do the BITE test of the weather radar AMM 34-41-00-740-002.

4. Fault Isolation
Subtask 34-41-00-810-072-A ** ON A/C NOT FOR ALL

A. If the BITE test gives the maintenance message RADAR 1 MOUNTING TRAY:

remove the XCVR-WEATHER RADAR, 1 [1SQ1] AMM 34-41-33-000-004
get access to the MTG TRAY-WR XCVR (9SQ) AMM 34-41-37-000-001
disconnect the electrical connector of the wave guide switch
do a check of the wiring between the WR transceiver 1 and the wave guide switch : pins AB/8D and A/C ASM 344101.

(1) If there is no continuity:

(2) If there is continuity:

do a check of the wiring of the weather radar transceiver mounting tray (9SQ):
. from pin A/F to the ground point
. from pin A/A to the weather radar control unit (3SQ), pin A/D
ASM 344101.

(a) If the wiring is not ok:

(b) If the wiring is ok:

1 If the fault continues:

replace the CTL UNIT-WEATHER RADAR [3SQ] AMM 34-41-12-000-001 and AMM 34-41-12-400-001.

a If the fault continues:

replace the weather radar transceiver 1 AMM 34-41-33-000-004 and AMM 34-41-33-400-003.

Subtask 34-41-00-810-072-B ** ON A/C NOT FOR ALL

A. If the BITE test gives the maintenance message WXR MOUNTING TRAY (9SQ):

remove the XCVR-WEATHER RADAR, 1 [1SQ1] AMM 34-41-33-000-004
get access to the MTG TRAY-WR XCVR (9SQ) AMM 34-41-37-000-001
disconnect the electrical connector of the wave guide switch
do a check of the wiring between the WR transceiver 1 and the wave guide switch : pins AB/8D and A/C ASM 344101.

(1) If there is no continuity:

(2) If there is continuity:

do a check of the wiring of the weather radar transceiver mounting tray (9SQ):
. from pin A/F to the ground point
. from pin A/A to the weather radar control unit (3SQ), pin A/D
ASM 344101.

(a) If the wiring is not ok:

(b) If the wiring is ok:

1 If the fault continues:

replace the CTL UNIT-WEATHER RADAR [3SQ] AMM 34-41-12-000-001 and AMM 34-41-12-400-001.

a If the fault continues:

replace the weather radar transceiver 1 AMM 34-41-33-000-004 and AMM 34-41-33-400-003.

Subtask 34-41-00-740-083-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:05 UTC