Drift of the Normal Brake Servovalve (Wheel 4)

TASK 32-42-00-810-847-A
Drift of the Normal Brake Servovalve (Wheel 4)

1. Possible Causes

SERVOVALVE-NORM BRK, WHEEL 4 [18GG]
PRESS XDCR-NORM BRK WHEEL 4 [14GG]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 32-42-00-810-958-A	Intermittent Electrical Failure of Normal Brake Servovalves 16GG & 18GG
AMM 32-42-21-000-001	Removal of the Normal-Brake Pressure Transducer
AMM 32-42-21-400-001	Installation of the Normal-Brake Pressure Transducer
AMM 32-42-48-000-001	Removal of the Normal Brake Servovalve
AMM 32-42-48-400-001	Installation of the Normal Brake Servovalve
AMM 32-46-00-740-005	BITE Test of BSCU - Normal Braking TEST

3. Fault Confirmation
Subtask 32-42-00-740-104-B

A. Do the BITE test of the Normal Braking System. AMM 32-46-00-740-005

4. Fault Isolation
Subtask 32-42-00-810-104-B

A. If the test gives the maintenance message BRK NORM SERVOVLV4 (18GG):

replace the SERVOVALVE-NORM BRK, WHEEL 4 [18GG] AMM 32-42-48-000-001 and AMM 32-42-48-400-001.

(1) If the fault continues:

replace the PRESS XDCR-NORM BRK WHEEL 4 [14GG] AMM 32-42-21-000-001 and AMM 32-42-21-400-001.

Subtask 32-42-00-740-105-A

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

NOTE: If there are intermittent faults on the normal brake servovalves 16GG and 18GG, you must do the trouble shooting task (Ref. TSM TASK 32-42-00-810-958).

[Rev.8 from Aug 2018] 2026.04.04 04:31:33 UTC