Temporary Loss of N1 Vibration Indication on Engine 1

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1. Possible Causes
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
77-30-00-810-821-A Loss of the N1 Vibration Indication on Engine 1
77-30-00-810-826-A High N1 Vibration Level on Engine 1
3. Fault Confirmation
Subtask 77-32-00-710-066-A
A. Test
Not applicable
4. Fault Isolation
PRE SB 73-1104 for A/C 0101-0102, 0951-0951
Subtask 77-32-00-810-066-A
A. If the fault sympton is identified by the crew observation: N1 vibration indication replaced by amber XX on
lower ECAM:
(1) Check if the failure message ENG1 SPEED SENSOR 4000EV is present on PFR
(a) If the failure message is present (Ref. TSM 77-30-00-810-821) .
(b) If the failure message is not present, go to step (2).
(2) Check the Engine Serial Number (ESN)
NOTE: If engine serial number displayed on MCDU is in the range between 13191 and 15000, then
add 5000 to this value to get the actual engine serial number.
(a) If ESN is V12220 or above, check if vibrations were perceived or suspected:
· if vibrations were perceived or suspected (Ref. TSM 77-30-00-810-826) .
· if vibrations were not perceived or suspected, no maintenance action is required and the
logbook entry can be closed.
(b) If ESN is below V12220, check if vibrations were perceived or suspected:
· if vibrations were perceived or suspected (Ref. TSM 77-30-00-810-826) .
· if vibrations were not perceived or suspected (Ref. TSM 77-30-00-810-821) .
** ON A/C
POST SB 73-1104 for A/C 0101-0102, 0951-0951
Subtask 77-32-00-810-066-B
A. If the fault sympton is identified by the crew observation: N1 vibration indication replaced by amber XX on
lower ECAM:
(1) Check if the failure message ENG1 SPEED SENSOR 4000EV is present on PFR
(a) If the failure message is present (Ref. TSM 77-30-00-810-821) .
(b) If the failure message is not present, go to step (2).
(2) Check the Engine Serial Number (ESN)
(a) If ESN is V12220 or above, check if vibrations were perceived or suspected:
· if vibrations were perceived or suspected (Ref. TSM 77-30-00-810-826) .
· if vibrations were not perceived or suspected, no maintenance action is required and the
logbook entry can be closed.
(b) If ESN is below V12220, check if vibrations were perceived or suspected:
· if vibrations were perceived or suspected (Ref. TSM 77-30-00-810-826) .
· if vibrations were not perceived or suspected (Ref. TSM 77-30-00-810-821) . [Rev.6 from Feb 2017] 2026.04.04 04:37:54 UTC