Emergency Lighting - Emergency Lighting in the Cabin does not come on when the EMER EXIT LT Switch is in the ON Position

TASK 33-51-00-810-810-A
Emergency Lighting - Emergency Lighting in the Cabin does not come on when the EMER EXIT LT Switch is in the ON Position

1. Possible Causes

SW-SIGNS/EMER EXIT LT [4WL]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 33-51-00-710-008	Operational Test of the Emergency Lighting in the Cabin with the 'EMER EXIT LT' Switch
ASM 335101

3. Fault Confirmation
Subtask 33-51-00-710-068-A

A. Do the operational test of the emergency lighting in the cabin by EMER EXIT LT switch AMM 33-51-00-710-008.

4. Fault Isolation
Subtask 33-51-00-810-059-A

A. If the emergency lighting in the cabin does not come on:

do a check of the SW-SIGNS/EMER EXIT LT [4WL] and replace it if necessary.

(1) If the fault continues:

do a check and repair the wiring between:
SW-SIGNS/EMER EXIT LT [4WL] switch pin 3A and POWER SUPPLY UNIT-EMERGENCY (10WL) connector A/A,
SW-SIGNS/EMER EXIT LT [4WL] switch pin 3B and GND,
SW-SIGNS/EMER EXIT LT [4WL] switch pin 1C and GND ASM 335101.

Subtask 33-51-00-710-069-A

B. Do the test given in Para. 3.

5. Close-up
Subtask 33-51-00-860-055-A

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:32:08 UTC