Loss of the Wheel Tachometer Signal for the SEC 3

TASK 27-94-00-810-822-A
Loss of the Wheel Tachometer Signal for the SEC 3

1. Possible Causes

wiring of ANI-6 signal from the SEC 3 (1CE3) to the related TACHOMETER-WHEEL
DRIVE ASSY-TACHOMETER
SEC-3 [1CE3]
TACHOMETER-WHEEL

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 27-94-00-810-904-A	Loss of the Wheel tachometer signal for the SEC with L/G control lever fault
ASM 279225
AMM 27-94-34-000-001	Removal of the SEC
AMM 27-94-34-400-001	Installation of the SEC
AMM 31-32-00-869-002	Procedure for the Class 3 Fault Reading
AMM 32-42-57-000-001	Removal of the Tachometer
AMM 32-42-57-400-001	Installation of the Tachometer
AMM 32-42-68-000-003	Removal of the MLG Tachometer-Drive
AMM 32-42-68-400-003	Installation of the MLG Tachometer-Drive

3. Fault Confirmation
Subtask 27-94-00-710-052-A

A. Test
Not applicable, you cannot confirm this fault on the ground.

4. Fault Isolation
Subtask 27-94-00-710-058-A

A. Do the steps that follow:
(1) On the CFDS MENU page, get access to the AVIONICS STATUS page AMM 31-32-00-869-002.
(2) Do a check of the STATUS report and look if the class 3 fault message L/G LEVER or L/G NORM CTL LEVER(6GA)/BSCU(10GG) is shown:

If the class 3 fault message L/G LEVER or L/G NORM CTL LEVER(6GA)/BSCU(10GG) is shown, do the trouble shooting procedure (Ref. TSM TASK 27-94-00-810-904).
If the class 3 fault message L/G LEVER or L/G NORM CTL LEVER(6GA)/BSCU(10GG) is not shown, continue this trouble shooting procedure.

Subtask 27-94-00-810-071-A

B. If the Post Flight Report gives the maintenance message:
SEC 3 OR INPUT OF WHEEL TACHOMETER

do a check and repair, if necessary, the wiring of ANI-6 signal from the SEC 3 (1CE3) to the related TACHOMETER-WHEEL for the SEC 3 COM part and MON part ASM 279225.

(1) If the wiring is correct:

examine the DRIVE ASSY-TACHOMETER of the related wheels.

(a) If the DRIVE ASSY-TACHOMETER is damaged:

replace it AMM 32-42-68-000-003 and AMM 32-42-68-400-003.

(b) If the DRIVE ASSY-TACHOMETER is not damaged and there is no report of brake temperature differences:

replace the SEC-3 [1CE3] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.

replace the TACHOMETER-WHEEL AMM 32-42-57-000-001 and AMM 32-42-57-400-001.

[Rev.8 from Aug 2018] 2026.04.04 04:28:13 UTC