Loss of the ADIRU Input Data to the Weather Radar Transceiver 1

TASK 34-41-00-810-814-A
Loss of the ADIRU Input Data to the Weather Radar Transceiver 1

1. Possible Causes

wiring of the DIGITAL ATT1 INP/ON SIDE bus from the weather radar transceiver 1 (1SQ1) to the first terminal block
wiring of the DIGITAL ATT3 INP/OFF SIDE bus from the weather radar transceiver 1 (1SQ1) to the first terminal block
wiring of the ATT HDG selector switch (13FP)
SEL SW-ATT HDG [13FP]
XCVR-WEATHER RADAR, 1 [1SQ1]

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 34-41-33-000-004	Removal of the Weather Radar Transceiver
AMM 34-41-33-400-003	Installation of the Weather Radar Transceiver

3. Fault Confirmation
Subtask 34-41-00-740-074-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the BITE test of the weather radar AMM 34-41-00-740-002.
(a) With the ATT HDG selector switch, on the SWITCHING panel, at NORM.
(b) With the ATT HDG selector switch at CAPT/3.

4. Fault Isolation
Subtask 34-41-00-810-066-A ** ON A/C NOT FOR ALL

A. If the BITE test gives the maintenance message RADAR 1 NO DATA FROM ADIRU:
(1) Only with the ATT HDG selector switch at NORM:

do a check and repair the wiring of the DIGITAL ATT1 INP/ON SIDE bus from the weather radar transceiver 1 (1SQ1) to the first terminal block ASM 344101.

(2) Only with the ATT HDG selector switch at CAPT/3:

do a check of the wiring of the DIGITAL ATT3 INP/OFF SIDE bus from the weather radar transceiver 1 (1SQ1) to the first terminal block ASM 344101.

(a) If there is no continuity:

repair the above wiring.

(b) If there is continuity:

do a check of the wiring of the ATT HDG selector switch (13FP):
. from pin A/14 to the weather radar transceiver 1 (1SQ1), pin AB/14G
. from pin A/13 to the ground point.
ASM 344101.

1 If there is no continuity:

repair the above wirings.

2 If there is continuity:

replace the SEL SW-ATT HDG [13FP] .

(3) With the ATT HDG selector switch at NORM and at CAPT/3:

replace the XCVR-WEATHER RADAR, 1 [1SQ1] AMM 34-41-33-000-004 and AMM 34-41-33-400-003.

Subtask 34-41-00-740-075-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

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