Failure of the N2 Higher than the Minimum TO Discrete Output on the EIU 1

TASK 73-25-00-810-863-A
Failure of the N2 Higher than the Minimum TO Discrete Output on the EIU 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 21-61-34-000-001	Removal of the Pack Controller
AMM 21-61-34-000-002	Removal of the Air-Conditioning System Controller
AMM 21-61-34-400-001	Installation of the Pack Controller
AMM 21-61-34-400-002	Installation of the Air-Conditioning System Controller
ASM 732509
AMM 73-25-34-000-040	Removal of the Engine Interface Unit (EIU)
AMM 73-25-34-400-040	Installation of the Engine Interface Unit (EIU)
AMM 73-25-34-710-040	Operational Test of the Engine Interface Unit
AMM 73-25-34-710-043	Operational Test of the Engine Interface Unit

3. Fault Confirmation
Subtask 73-25-00-710-174-A ** ON A/C NOT FOR ALL

A. Do the operational test of the engine interface unit through the CFDS AMM 73-25-34-710-040.

Subtask 73-25-00-710-174-B ** ON A/C NOT FOR ALL

A. Do the operational test of the engine interface unit through the CFDS AMM 73-25-34-710-043.

4. Fault Isolation
Subtask 73-25-00-810-112-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message CHECK PACK CONT 7HH EIU 1 CIRCUIT:

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the EIU-1 (1KS1) to the pack 1 temperature controller (7HH) pin AB/1G to pin AA/10B ASM 732509.

Subtask 73-25-00-810-112-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message CHECK PACK CONT 7HH/EIU1 CIRCUIT:

NOTE: CONT-PACK (7HH) has been replaced by AIR COND SYS 1 (47HH) due to a modification of the Air Conditioning System.

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the EIU-1 (1KS1) to the pack 1 temperature controller (47HH) pin AB/1G to pin AB/3C ASM 732509.

Subtask 73-25-00-710-175-A ** ON A/C NOT FOR ALL

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

[Rev.8 from Aug 2018] 2026.04.04 04:35:43 UTC