LCD Monitor Failure

TASK 23-72-00-810-807-A
LCD Monitor Failure

1. Possible Causes

MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA]
CKPT DOOR VIDEO pushswitch (17RA)
wiring
C/B-DOORS/CKPT/VIDEO/SPLY [15RA]
HINGE- MONITOR [10-RA--A]
VIDEO PUSHSWITCH (16RA)
CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 23-72-00-710-001	Operational Test of the Anti-Hijack Camera-Monitoring-System
AMM 23-72-22-000-001	Removal of the Cockpit-Door Surveillance-System Monitor
AMM 23-72-22-400-001	Installation of the Cockpit-Door Surveillance-System Monitor
AMM 52-51-00-710-002	Operational Test of the Cockpit-Door Locking System (CDLS)

3. Fault Confirmation
Subtask 23-72-00-710-055-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the operational test of the Cockpit Door Surveillance System (CDSS) AMM 23-72-00-710-001.

4. Fault Isolation
Subtask 23-72-00-810-065-A ** ON A/C NOT FOR ALL

A. If the images for cameras 1, 2 and 3 do not show on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] :

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

(1) If the fault continues and the green LED on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] is off:

push the CKPT DOOR VIDEO pushswitch, on panel 271VU in the cockpit.

(a) If the OFF legend in the CKPT DOOR VIDEO pushswitch does not come on:

replace the CKPT DOOR VIDEO pushswitch (17RA).

(b) If the fault continues:

do a check for 28VDC at pin A3 on the CKPT DOOR VIDEO pushswitch (17RA).

1 If there is not 28VDC:

do a check and repair the wiring between the CKPT DOOR VIDEO pushswitch (17RA) and the circuit breaker C/B-DOORS/CKPT/VIDEO/SPLY [15RA] .

2 If there is 28VDC at pin A3:

do a check for 28VDC at pin 42 on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] and if necessary repair the related wiring .

3 If there is 28VDC at pin 42:

do a check for a ground signal at pin 21 on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] and if necessary repair the related wiring .

(2) If the fault continues and the green LED on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] is on:

do a check and if necessary repair the related wiring between the cameras 1, 2 and 3 and the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] .

Subtask 23-72-00-810-066-A ** ON A/C NOT FOR ALL

B. If the pictures on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] do not change from camera 1 to cameras 2 and 3 when the VIDEO pushswitch in the cockpit is pushed:

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] AMM 23-72-22-000-001 AMM 23-72-22-400-001.

(1) If the fault continues:

replace the HINGE- MONITOR [10-RA--A] AMM 23-72-22-000-001 AMM 23-72-22-400-001.

(2) If the fault continues:

replace the VIDEO PUSHSWITCH (16RA).

(a) If the fault continues:

do a check and if necessary repair the wiring between the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , and the VIDEO PUSHSWITCH (16RA).

Subtask 23-72-00-810-067-A ** ON A/C NOT FOR ALL

C. If the images for cameras 1, 2 and 3 are bad/distorted/too dim/too bright MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] :

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

Subtask 23-72-00-810-068-A ** ON A/C NOT FOR ALL

D. If the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] does not go into the power-down-mode:

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

Subtask 23-72-00-810-069-A ** ON A/C NOT FOR ALL

E. If the incorrect images are shown on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] when the power-down-mode is excited:

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

Subtask 23-72-00-810-070-A ** ON A/C NOT FOR ALL

F. If the images from camera 1 do not show on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] when cockpit entry is requested:

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

(1) If the fault continues:

do a check and if necessary repair the wiring between the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] and the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] .

(2) If the fault continues:

do the test of the Cockpit Door Lock System AMM 52-51-00-710-002. Make sure that the images from camera 1 show on the screen of the LCD monitor when cockpit entry is requested.

(a) If the images from camera 1 do not show when cockpit entry is requested:

do the related trouble shooting for the cockpit door lock system. You must do the trouble shooting to make sure that there is a signal from the CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM or CONTROL UNIT-COCKPIT DOOR LOCKING SYSTEM [24MQ] to the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] when cockpit access is requested.

Subtask 23-72-00-810-071-A ** ON A/C NOT FOR ALL

G. If the failure history is not correctly shown on the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] :

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

Subtask 23-72-00-810-072-A ** ON A/C NOT FOR ALL

H. If the failure history cannot be deleted from the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] :

replace the MONITOR- COCKPIT DOOR SURVEILLANCE SYSTEM [10RA] , AMM 23-72-22-000-001 and AMM 23-72-22-400-001.

Subtask 23-72-00-700-055-A ** ON A/C NOT FOR ALL

I. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:48 UTC