Cabin Lights - One Cabin Light cannot be dimmed or switched off or dims incorrectly

TASK 33-21-00-810-803-A
Cabin Lights - One Cabin Light cannot be dimmed or switched off or dims incorrectly

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 23-73-00-740-005	BITE-Test of the Cabin Intercommunication Data System (CIDS) through the CFDS
AMM 23-73-46-000-001	Removal of the Decoder/Encoder Unit A (200RH)
AMM 23-73-46-400-001	Installation of the Decoder/Encoder Unit A (200RH)
AMM 33-21-00-710-001	Operational Test of the General Illumination
ASM 332101
ASM 332102
AMM 33-21-11-000-001	Removal of the Ballast Unit, Lampholder and Fluorescent Tube
AMM 33-21-11-000-802	Removal of the Cabin LED Unit (CLEDU)
AMM 33-21-11-400-001	Installation of the Ballast Unit, Lampholder and Fluorescent Tube
AMM 33-21-11-400-802	Installation of the Cabin LED Unit (CLEDU)

3. Fault Confirmation
Subtask 33-21-00-710-052-A

A. Do the BITE-test of the Cabin Intercommunication Data-System (CIDS) AMM 23-73-00-740-005.

Subtask 33-21-00-710-059-A

B. Do the operational test of the general illumination AMM 33-21-00-710-001.

4. Fault Isolation
Subtask 33-21-00-810-052-A

A. If the test gives a maintenance message, do the trouble shooting procedure related to the maintenance message.

Subtask 33-21-00-810-057-A ** ON A/C NOT FOR ALL

B. If there is no CFDS message, but you cannot control one light correctly:

(1) If the fault continues:

do a check and repair the WIRING between the related:
BALLAST UNIT connector A/D and DEU-A connector B/1,B/4,B/9 or B/12,
BALLAST UNIT connector A/E and DEU-A connector B/2,B/5,B/10 or B/13,
BALLAST UNIT connector A/F and DEU-A connector B/3,B/6,B/11 or B/14
ASM 332101 and ASM 332102.

(2) If the fault continues:

Subtask 33-21-00-810-057-B ** ON A/C NOT FOR ALL

B. If there is no CFDS message, but you cannot control one light correctly:

(1) If the fault continues:

do a check and repair the WIRING between the related:
CLEDU connector A/5 and DEU-A connector B/1,B/4,B/7,B/10,B14,B/17,B20 or B/23,
CLEDU connector A/6 and DEU-A connector B/2,B/5,B/8,B/11,B15,B/18,B21 or B/24 ASM 332101 and ASM 332102.

(2) If the fault continues:

Subtask 33-21-00-710-060-A

C. Do the test as given in the Para. 3.A .

5. Close-up
Subtask 33-21-00-860-052-A

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:31:54 UTC