Failure of the alternate braking system

TASK 32-43-00-810-829-A
Failure of the alternate braking system

1. Possible Causes

ABCU [95GG]
PRESS XDCR-NORM BRK SPLY [96GG]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 32-42-22-000-001	Removal of the Normal-Brake Supply Pressure-Transducer
AMM 32-42-22-400-001	Installation of the Normal-Brake Supply Pressure-Transducer
AMM 32-43-00-710-002	Operational Check to start the Functional Test of the Alternate Braking Automatically (flight simulated)
ASM 324302
AMM 32-43-34-000-001	Removal of the Alternate Braking Control Unit (ABCU)
AMM 32-43-34-400-001	Installation of the Alternate Braking Control Unit (ABCU)

3. Fault Confirmation
Subtask 32-43-00-740-076-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the operational check to start the functional test of the Alternate Braking automatically (flight simulated) AMM 32-43-00-710-002.

4. Fault Isolation
Subtask 32-43-00-810-078-A ** ON A/C NOT FOR ALL

A. If the operational check gives the maintenance message ABCU(95GG)/BRK NORM SEL VALVE PRESS XDCR (96GG) and the TROUBLE SHOOTING DATA gives the fault code 1540:
(1) Read the trouble shooting data of the fault code 1540.
(2) Do a check of the Alternate Pressure Transducer Left (APTL) and the Alternate Pressure Transducer Right (APTR) pressure values and if they are less than 30 bar (435.1131 psi):

replace the ABCU [95GG] AMM 32-43-34-000-001 AMM 32-43-34-400-001

(3) If the fault continues:

replace the PRESS XDCR-NORM BRK SPLY [96GG] AMM 32-42-22-000-001 AMM 32-42-22-400-001

(4) If the fault continues:

do a check and repair the wiring between the ABCU (95GG) and the pressure transducer (96GG) ASM 324302.

Subtask 32-43-00-740-077-A ** ON A/C NOT FOR ALL

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

[Rev.8 from Aug 2018] 2026.04.04 04:31:41 UTC