Loss of the SDAC1 Input Signal Detected by the ATSU

TASK 46-21-00-810-837-A
Loss of the SDAC1 Input Signal Detected by the ATSU

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-55-34-000-001	Removal of the SDAC
AMM 31-55-34-400-001	Installation of the SDAC
AMM 46-21-00-740-001	BITE Test of the ATIMS
ASM 462105
AMM 46-21-34-000-001	Removal of the Air Traffic Service Unit (ATSU)
AMM 46-21-34-400-001	Installation of the Air Traffic Service Unit (ATSU)

3. Fault Confirmation
Subtask 46-21-00-740-120-A

A. Test
(1) Do the BITE test of the ATIMS AMM 46-21-00-740-001.

4. Fault Isolation
Subtask 46-21-00-810-085-A

A. If the test gives the maintenance message SDAC1(1WV1)/ATSU1(1TX1):

(1) If the fault continues:

(a) If the fault continues:

remove the SDAC 1 and the ATSU
do a check and repair the wiring of the SDAC 1 DATA BUS : between pins AB/8J,8K of the SDAC 1 and pins AA/6G,6H of the ATSU ASM 462105
install the SDAC 1 and the ATSU.

Subtask 46-21-00-740-121-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:20 UTC