Loss of the Output 1 Bus of the ECU 1 Channel B

TASK 73-29-00-810-830-A
Loss of the Output 1 Bus of the ECU 1 Channel B

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-50-00-710-001	Ground Scanning of the Central Warning System
AMM 73-21-60-000-001	Removal of the Electronic Control Unit (ECU)
AMM 73-21-60-400-001	Installation of the Electronic Control Unit (ECU)
ASM 732510

3. Fault Confirmation
Subtask 73-29-00-710-080-A ** ON A/C NOT FOR ALL

A. Do the operational test of the Central Warning Systems AMM 31-50-00-710-001.

4. Fault Isolation
Subtask 73-29-00-810-086-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message FWC2 : NO DATA FROM ECU 1B:

(1) If the fault continues:

do a check and repair the aircraft wiring of the output 1 bus on channel B from the ECU (4000KS) to the first terminal block ASM 732510.

Subtask 73-29-00-710-081-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:35:54 UTC