An aircraft maintenance technician (amt) and two pilots report about the confusion surrounding an ME...

Narrative:

Had a write-up that stated during light test; emergency lights 'unarmed' light not 'on' [not illuminated]. Works ok when switch is 'off'. Light did not test in 'armed' postion. Emergency lights in aircraft worked normally. I was in the process of trying to order a new emergency light panel assembly when another aircraft maintenance technician (amt) brought to my attention a wiring diagram manual (wdm) 33-51-11 that showed that this was a normal condition and that the maintenance controller agreed and signed it off. However; I found out the next day that there was another problem with the 'unarmed' emergency light and the light assembly was replaced and it now tested normal. I do not remember the name of the controller who agreed that it was a normal condition. Also; when I returned to work; I consulted with another amt and he told me that the light should have tested in the 'armed' postion after looking at the wire diagram more carefully.

Original NASA ASRS Text

Title: An Aircraft Maintenance Technician (AMT) and two pilots report about the confusion surrounding an MEL deferral of an Emergency Lights 'Unarmed' light not illuminating during a preflight lights test procedure on a B757 aircraft; with the Emergency Lights switch in the 'Armed' position.

Narrative: Had a write-up that stated during light test; Emergency Lights 'Unarmed' light not 'On' [not illuminated]. Works OK when switch is 'Off'. Light did not test in 'Armed' postion. Emergency lights in aircraft worked normally. I was in the process of trying to order a new Emergency Light Panel Assembly when another Aircraft Maintenance Technician (AMT) brought to my attention a Wiring Diagram Manual (WDM) 33-51-11 that showed that this was a normal condition and that the Maintenance Controller agreed and signed it off. However; I found out the next day that there was another problem with the 'Unarmed' Emergency Light and the Light Assembly was replaced and it now tested normal. I do not remember the name of the Controller who agreed that it was a normal condition. Also; when I returned to work; I consulted with another AMT and he told me that the light should have tested in the 'Armed' postion after looking at the wire diagram more carefully.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1120370
Time
Date	201310
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Emergency Exit Lighting
Person 1
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Person 2
Function	Captain
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

An aircraft maintenance technician (amt) and two pilots report about the confusion surrounding an MEL deferral of an emergency lights 'unarmed' light not illuminating during a preflight lights test procedure on a B757 aircraft; with the emergency lights switch in the 'armed' position.