DOC AIRBUS | TSM A320FN1/N2 Mismatch on the Same Engine, on Engine 1 or 2
TASK 77-00-00-810-858-A
N1/N2 Mismatch on the Same Engine, on Engine 1 or 2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 77-00-00-710-141-A ** ON A/C NOT FOR ALL
Subtask 77-00-00-810-115-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:33 UTC
N1/N2 Mismatch on the Same Engine, on Engine 1 or 2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 73-20-00-810-919-A | Loss of the ADIRU input Data through the Channel A or disagree between Aircraft and Engine sensors on Engine 1 |
| TSM TASK 73-20-00-810-920-A | Loss of the ADIRU input Data through the Channel A or disagree between Aircraft and Engine sensors on Engine 2 |
| TSM TASK 73-20-00-810-961-A | Loss of the ADIRU input Data through the Channel B or disagree between Aircraft and Engine sensors on Engine 1 |
| TSM TASK 73-20-00-810-962-A | Loss of the ADIRU input Data through the Channel B or disagree between Aircraft and Engine sensors on Engine 2 |
| AMM 71-00-00-710-006 | Minimum Idle Check |
| AMM 73-29-00-710-040 | Operational Test of the FADEC on the ground (with Engine Motoring) |
| AMM 75-31-00-210-001 | Visual Inspection of the Variable Bleed Valve (VBV) System |
| AMM 75-31-00-210-002 | Visual Inspection of the Variable Bleed Valve (VBV) System |
Subtask 77-00-00-710-141-A ** ON A/C NOT FOR ALL
A. Test
(1) Not applicable, the fault is evident.
4. Fault Isolation(1) Not applicable, the fault is evident.
Subtask 77-00-00-810-115-A ** ON A/C NOT FOR ALL
A. If the fault symptom is identified by the crew observation: ENG1-N1/N2 mismatch on the same engine:
(1) Do an operational test of the FADEC on the ground (with engine motoring) to do a check of the VSV/VBV position AMM 73-29-00-710-040.
(2) Do a visual inspection of the variable bleed valve system to do a check of the VBV doors position AMM 75-31-00-210-001.
Subtask 77-00-00-810-115-C ** ON A/C NOT FOR ALL (1) Do an operational test of the FADEC on the ground (with engine motoring) to do a check of the VSV/VBV position AMM 73-29-00-710-040.
(2) Do a visual inspection of the variable bleed valve system to do a check of the VBV doors position AMM 75-31-00-210-001.
A. If the fault symptom is identified by the crew observation: ENG1-N1/N2 mismatch on the same engine:
(1) Do a check of the Post Flight Report (PFR) and the Scheduled Maintenance report (SMR)/class 3 for P0/P12/T12, ADC, ECU:
(a) If the failure message is present, do the related troubleshoot procedure (Ref. TSM TASK 73-20-00-810-919) or (Ref. TSM TASK 73-20-00-810-920) or (Ref. TSM TASK 73-20-00-810-961) or (Ref. TSM TASK 73-20-00-810-962).
(b) If the failure message is not present:
1 Do an operational test of the FADEC on the ground (with engine motoring) to do a check of the VSV/VBV position AMM 73-29-00-710-040.
2 Do a visual inspection of the variable bleed valve system to do a check of the VBV doors position AMM 75-31-00-210-002.
Subtask 77-00-00-710-142-A ** ON A/C NOT FOR ALL (1) Do a check of the Post Flight Report (PFR) and the Scheduled Maintenance report (SMR)/class 3 for P0/P12/T12, ADC, ECU:
(a) If the failure message is present, do the related troubleshoot procedure (Ref. TSM TASK 73-20-00-810-919) or (Ref. TSM TASK 73-20-00-810-920) or (Ref. TSM TASK 73-20-00-810-961) or (Ref. TSM TASK 73-20-00-810-962).
(b) If the failure message is not present:
1 Do an operational test of the FADEC on the ground (with engine motoring) to do a check of the VSV/VBV position AMM 73-29-00-710-040.
2 Do a visual inspection of the variable bleed valve system to do a check of the VBV doors position AMM 75-31-00-210-002.