C. If a blank screen is shown on the FO ND DU:
- replace the ND-F/O (3WT2) (Ref. AMM TASK 31-63-22-000-001) and (Ref. AMM TASK 31-63-22-400-001).
(1) If the fault continues:
(a) Do a check for 115VAC at pin AA-79 of the FO ND DU (Ref. ASM 31-61/02)
1 If there is no 115VAC:
_
- check the wiring from the ND FO SPLY-C/B (12WT2) to the FO ND-DU(3WT2) pin AA-79 (Ref. ASM 31-61/01)
a if there is no continuity:
_
- repair the wiring
b If there is continuity:
_
- replace the EIS/ND/F/O (12WT2). 2 If there is 115VAC:
_
- do a check for a ground signal at pin A-77 of the FO ND DU a If there is no ground signal:
_
- check and repair the wiring from the FO ND-DU pin AA-77 to the the ground terminal
b If there is a ground signal:
_
- do a check for 28VDC at the FO ND-DU pin AA-81 . if there is no 28VDC, check and repair the wiring from the FO ND-DU pin AA-81 to the FO ND-SWTG C/B (23WT2) . if there is 28VDC, replace the EIS/ND/F/O/SWTG (23WT2).
(2) If the fault continues:
- do a check for a ground signal at pin AA-75 of the FO ND DU.
(a) If there is a ground signal:
- make sure there is no ground signal at pin 8 of the FO ND potentiometer (8WT2)
1 If there is no ground signal:
_
- check and repair the wiring from the FO ND-POT (8WT2) pin 8 to the FO ND-DU (3WT2) pin AA-75.
2 If there is a ground signal:
_ - replace the POT-ND, F/O (8WT2).
5. Close-up
________
A. CLose-up
- Do the EIS Stop Procedure (Ref. AMM TASK 31-60-00-860-002).
Blank Screen on the Upper ECAM DU
1. Possible Causes
_______________
- DU-ECAM, UPPER (4WT1)
- EIS/ECAM DU/UPPER/SPLY (13WT1)
- EIS/ECAM DU/UPPER/SWTG (24WT1)
- CTL PNL-ECAM (6WT)
- wiring
2. Job Set-up Information
______________________
A. Referenced Information
-------------------------------------------------------------------------------REFERENCE DESIGNATION -------------------------------------------------------------------------------
AMM 31-60-00-860-001 EIS Start Procedure AMM 31-60-00-860-002 EIS Stop Procedure AMM 31-63-22-000-001 Removal of the Display Unit
(2WT1,2WT2,3WT1,3WT2,4WT1,4WT2) AMM 31-63-22-400-001 Installation of the Display Unit
(2WT1,2WT2,3WT1,3WT2,4WT1,4WT2) ASM 31-61/02 ASM 31-68/01
3. Fault Confirmation
__________________
A. Job Set-up
(1) Do the EIS start procedure (Ref. AMM TASK 31-60-00-860-001).
4. Fault Isolation
_______________
A. If the operational image is shown on the upper ECAM DU:
- no maintenance action is necessary.
B. If a maintenance message is shown on a black screen
- do the fault isolation procedure relative to this message.
C. If a blank screen is shown on the upper ECAM DU:
- replace the DU-ECAM, UPPER (4WT1) (Ref. AMM TASK 31-63-22-000-001) and (Ref. AMM TASK 31-63-22-400-001).
(1) If the fault continues:
(a) Do a check for 115VAC at pin AA-79 of the upper ECAM DU (Ref. ASM 31-61/02)
1 If there is no 115VAC:
_
- check the wiring from the upper ECAM SPLY-C/B (13WT1) to the upper ECAM DU(4WT1) pin AA-79 (Ref. ASM 31-68/01)
a If there is no continuity:
_ - repair the wiring
b If there is continuity:
_
- replace the EIS/ECAM DU/UPPER/SPLY (13WT1).
2 If there is 115VAC:
_
- do a check for a ground signal at pin A-77 of the upper ECAM DU
a If there is no ground signal:
_
- check and repair the wiring from the upper ECAM-DU pin AA-77 to the the ground terminal
b If there is a ground signal:
_
- do a check for 28VDC at the upper ECAM-DU pin AA-81 . if there is no 28VDC, check and repair the wiring from the upper ECAM-DU pin AA-81 to the upper ECAM DU -SWTG C/B (24WT1) . if there is 28VDC, replace the EIS/ECAM DU/UPPER/SWTG (24WT1).
(2) If the fault continues:
- do a check for a ground signal at pin AA-75 of the upper ECAM DU
(a) If there is a ground signal:
- make sure there is no ground signal at pin B-D of the upper ECAM DU potentiometer (6WT1)
1 If there is no ground signal:
_
- check and repair the wiring from the upper ECAM DU potentiometer (6WT1) pin B-D to the upper ECAM DU (4WT1) pin AA-75. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A320 Trouble Shooting Manual 排故手册 指示和记录系统 3(121)
