Loss of the REV Indication in the Thrust Reverser Deployed Position on Engine 1

TASK 78-00-00-810-803-A
Loss of the REV Indication in the Thrust Reverser Deployed Position on Engine 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ASM 732516
AMM 78-30-00-040-040	Deactivation of the Thrust Reverser System
AMM 78-31-00-710-040	Operational Test of the Thrust Reverser System
AMM 78-31-00-710-042	Operational Test of the Thrust Reverser System
AMM 78-31-51-000-040	Removal of the Hydraulic Control Unit
AMM 78-31-51-400-040	Installation of the Hydraulic Control Unit

3. Fault Confirmation
Subtask 78-00-00-710-054-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the operational test of the thrust reverser system AMM 78-31-00-710-040.

Subtask 78-00-00-710-054-B ** ON A/C NOT FOR ALL

A. Test
(1) Do the operational test of the thrust reverser system AMM 78-31-00-710-042.

4. Fault Isolation
Subtask 78-00-00-810-053-A ** ON A/C NOT FOR ALL

A. If the test confirms the fault:

do a check to make sure that the thrust reverser system is not inhibited AMM 78-30-00-040-040.

(1) If the system is not inhibited:
(a) Do a check and repair the aircraft wiring between:

the throttle control unit (8KS1)/ECU (4000KS)/HCU (4101KS) and
the throttle control unit (8KS1)/SEC (1CE1) (1CE2)/EIU 1 (1KS1)/thrust reverser inhibition relay (14KS1) ASM 732516.

(2) If the fault continues:

do a check to make sure that there is a hydraulic pressure supply from the aircraft.

(3) If the fault continues:

(4) If the fault continues:

replace the HCU-THRUST REV (4101KS) AMM 78-31-51-000-040 and AMM 78-31-51-400-040.

Subtask 78-00-00-710-055-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.A.

[Rev.8 from Aug 2018] 2026.04.04 04:37:58 UTC