Unwanted (Spurious) Warning/Indication on Upper ECAM DU without HUD Installed

TASK 31-55-00-810-802-A
Unwanted (Spurious) Warning/Indication on Upper ECAM DU without HUD Installed

1. Possible Causes

wiring
SDAC-1 [1WV1]
SDAC-2 [1WV2]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-36-00-740-008	Access to the Parameter Call-Up Menus
ASM 315407
AMM 31-55-34-000-001	Removal of the SDAC
AMM 31-55-34-400-001	Installation of the SDAC

3. Fault Confirmation
Subtask 31-55-00-710-051-A

A. Not applicable, the fault is evident.

4. Fault Isolation
Subtask 31-55-00-810-051-A

A. If the 'NAV HUD FAULT' warning message is shown on the upper ECAM DU when the HUD is not installed:

NOTE: This procedure is only applicable to SDAC with P/N prior to 350E5500204 (standard H2/E2).

(1) Get access to the Parameter Call-up menus AMM 31-36-00-740-008.

NOTE: Label 005 SDI 00 Bit 14 must be at 1 if HUD is not installed.

(a) Compare the SDAC1 and SDAC2 pin programming with the state of the aircraft pin programming given in the ASM 315407.

NOTE: 1WV1(2) pin AE/2C must not be connected to the ground if HUD is not installed.

1 If the pin programming is incorrect:
. repair the aircraft wiring .
2 If the pin programming is correct:
. replace the SDAC related to the fault
SDAC-1 [1WV1] or SDAC-2 [1WV2] AMM 31-55-34-000-001 and AMM 31-55-34-400-001.

[Rev.8 from Aug 2018] 2026.04.04 04:30:35 UTC