Failure of the Nose Wheel Steering Servo-Control or Incorrect Ajustment of the Nose Wheel Steering Gearbox

TASK 32-51-00-810-844-A
Failure of the Nose Wheel Steering Servo-Control or Incorrect Ajustment of the Nose Wheel Steering Gearbox

1. Possible Causes

SERVO CTL-N/W STEERING [6GC]
SENSOR-N/W STRG FDBK,CTL CHAN [3GC]
SENSOR-N/W STRG FDBK,MONITORING CHAN [4GC]
BSCU [10GG]
wiring from the BSCU (10GG) to the nose wheel steering servo-control (6GC)
wiring from the BSCU (10GG) to the feedback sensor (3GC)
wiring from the BSCU (10GG) to the feedback sensor (4GC)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 32-42-34-000-001	Removal of the Braking/Steering Control Unit (BSCU)
AMM 32-42-34-400-001	Installation of the Braking/Steering Control Unit (BSCU)
AMM 32-46-00-740-001	BITE Test of the BSCU
ASM 325101
AMM 32-51-19-000-001	Removal of the Nose Wheel Steering Feedback Sensor P/N C24763000
AMM 32-51-19-400-001	Installation of the Nose Wheel Steering Feedback Sensor P/N C24763000
AMM 32-51-51-000-001	Removal of the Nose-Wheel Steering Servo-Control
AMM 32-51-51-000-002	Removal of the Nose Wheel Steering Servo-Valve
AMM 32-51-51-400-001	Installation of the Nose-Wheel Steering Servo-Control
AMM 32-51-51-400-002	Installation of the Nose Wheel Steering Servo-Valve

3. Fault Confirmation
Subtask 32-51-00-740-111-A ** ON A/C NOT FOR ALL

A. Test
(1) Do a reset of the BSCU with the A/SKID AND NOSE WHEEL switch (5GG).
(2) Do the BITE test of the BSCU AMM 32-46-00-740-001.

4. Fault Isolation
Subtask 32-51-00-810-107-A ** ON A/C NOT FOR ALL

A. Read the CLASS 3 FAULT report and if the STEERING ELECTRO-HYD MODULE (6GC) maintenance message is shown:

do a check for water in the electrical connector of the nose wheel steering servo-control (6GC) ASM 325101.

(1) If there is water:

examine the electrical connector for corrosion.

(a) If there is corrosion:

replace the SERVO CTL-N/W STEERING [6GC] AMM 32-51-51-000-001 and AMM 32-51-51-400-001.

(b) If there is no corrosion:

dry the electrical connector of the nose wheel steering servo-control (6GC) and connect it.

(2) If there is no water:

remove the nose wheel steering servo-valve AMM 32-51-51-000-002
do a check for water in the two electrical connectors of the nose wheel steering servo-control.

(a) If there is water:

examine the electrical connectors for corrosion.

1 If there is corrosion:

replace the SERVO CTL-N/W STEERING [6GC] AMM 32-51-51-000-001 and AMM 32-51-51-400-001.

2 If there is no corrosion:

dry the two electrical connectors and install the nose wheel steering servo-valve AMM 32-51-51-400-002.

(b) If there is no water:

install the nose wheel steering servo-valve AMM 32-51-51-400-001.

1 If the fault continues:

Continue the trouble shooting at step 4.A.(3).

(3) If the fault continues:

replace the SENSOR-N/W STRG FDBK,CTL CHAN [3GC] AMM 32-51-19-000-001 and AMM 32-51-19-400-001.

(a) If the fault continues:

replace the SENSOR-N/W STRG FDBK,MONITORING CHAN [4GC] AMM 32-51-19-000-001 and AMM 32-51-19-400-001.

1 If the fault continues:

replace the BSCU [10GG] AMM 32-42-34-000-001 and AMM 32-42-34-400-001.

a If the fault continues:

do a check and repair the wiring from the BSCU (10GG) to the nose wheel steering servo-control (6GC) pins AB/12E, 12F, 13E, 13F, 14E, 14F to pins A/G, H, E, F, C, D ASM 325101.

b If the fault continues:

do a check and repair the wiring from the BSCU (10GG) to the feedback sensor (3GC) pins AB/15E, 15F, 8E, 8F, 9F, 9E to pins A/A, B, C, D, E, F ASM 325101.

c If the fault continues:

do a check and repair the wiring from the BSCU (10GG) to the feedback sensor (4GC) pins AB/14E, 14F, 10E, 10F, 11F, 11E to pins A/A, B, C, D, E, F ASM 325101.

Subtask 32-51-00-740-112-A ** ON A/C NOT FOR ALL

B. Test
(1) Do the test given in Para. 3.A.

[Rev.8 from Aug 2018] 2026.04.04 04:31:51 UTC