DOC AIRBUS | TSM A320FN1 Indication Disagreement between DMC Reading and FWC Feedback
TASK 77-00-00-810-941-A
N1 Indication Disagreement between DMC Reading and FWC Feedback
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 77-00-00-710-304-A ** ON A/C NOT FOR ALL
Subtask 77-00-00-810-269-A ** ON A/C NOT FOR ALL
Subtask 77-00-00-860-117-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:51 UTC
N1 Indication Disagreement between DMC Reading and FWC Feedback
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 31-53-34-000-001 | Removal of the Flight Warning Computer (FWC) |
| AMM 31-53-34-400-001 | Installation of the Flight Warning Computer (FWC) |
| AMM 31-63-34-000-001 | Removal of the DMC |
| AMM 31-63-34-400-001 | Installation of the DMC |
| AMM 71-00-00-720-811 | Test No. 3 - Idle Power Test |
| AMM 73-21-01-000-801 | Removal of the Electronic Engine Control (EEC) |
| AMM 73-21-01-400-801 | Installation of the Electronic Engine Control (EEC) |
Subtask 77-00-00-710-304-A ** ON A/C NOT FOR ALL
A. Test
(1) Not Applicable
4. Fault Isolation(1) Not Applicable
Subtask 77-00-00-810-269-A ** ON A/C NOT FOR ALL
A. Do as follows:
(1) On Post Flight Report (PFR) and/or ground report, do a check for N1 SNSR FAIL fault or N1 SNSR DISAGREE fault.
(a) Troubleshoot these faults first
(b) Do the test given in Para. 4.B.
(2) If the fault continues:
(a) Replace DMC-1 [1WT1] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.
(b) Do the test given in Para. 4.B.
(3) If the fault continues:
(a) Replace DMC-2 [1WT2] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.
(b) Do the test given in Para. 4.B.
(4) If the fault continues:
(a) Replace DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.
(b) Do the test given in Para. 4.B.
(5) If the fault continues:
(a) Replace FWC-1 [1WW1] AMM 31-53-34-000-001 and AMM 31-53-34-400-001.
(b) Do the test given in Para. 4.B.
(6) If the fault continues:
(a) Replace FWC-2 [1WW2] AMM 31-53-34-000-001 and AMM 31-53-34-400-001.
(b) Do the test given in Para. 4.B.
(7) If the fault continues:
(a) Replace
(b) Do the test given in Para. 4.B.
Subtask 77-00-00-710-308-A ** ON A/C NOT FOR ALL (1) On Post Flight Report (PFR) and/or ground report, do a check for N1 SNSR FAIL fault or N1 SNSR DISAGREE fault.
(a) Troubleshoot these faults first
(b) Do the test given in Para. 4.B.
(2) If the fault continues:
(a) Replace DMC-1 [1WT1] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.
(b) Do the test given in Para. 4.B.
(3) If the fault continues:
(a) Replace DMC-2 [1WT2] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.
(b) Do the test given in Para. 4.B.
(4) If the fault continues:
(a) Replace DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.
(b) Do the test given in Para. 4.B.
(5) If the fault continues:
(a) Replace FWC-1 [1WW1] AMM 31-53-34-000-001 and AMM 31-53-34-400-001.
(b) Do the test given in Para. 4.B.
(6) If the fault continues:
(a) Replace FWC-2 [1WW2] AMM 31-53-34-000-001 and AMM 31-53-34-400-001.
(b) Do the test given in Para. 4.B.
(7) If the fault continues:
(a) Replace
(b) Do the test given in Para. 4.B.
B. Test
(1) Do a minimum idle check to make sure that all engine instruments give the correct indication AMM 71-00-00-720-811.
5. Close-up(1) Do a minimum idle check to make sure that all engine instruments give the correct indication AMM 71-00-00-720-811.
Subtask 77-00-00-860-117-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(1) Make sure that the work area is clean and clear of tools and other items.