A line mechanic reports the need to clarify the intent of the MEL language in MEL chapter 33-23a; re...

Narrative:

November 2009; I issued MEL 33-01a for cockpit lighting; due to a portion of the lights not reacting to the dimming switch. A few days later; a pilot flying from ZZZ called and said he thought the MEL should be 33-23a; which is the master dim system. At his request the MEL was reclassified. The captain believed it was incorrect so it was reclassified per his request. Interpretation of which MEL applied was the issue. When the captain called to reclassify the MEL; it was determined that by doing so; it was a 'drop dead' MEL due to time limits from the date of discovery. Clarification of the intent of the MEL (is needed). Do they mean any part of the system or the complete (master) dim test function?

Original NASA ASRS Text

Title: A Line Mechanic reports the need to clarify the intent of the MEL language in MEL Chapter 33-23a; regarding the Cockpit lighting Master Dim System; compared to MEL 33-01a. A portion of the Cockpit lights were not reacting to the Dimming switch and confusion arose as to which MEL applied.

Narrative: November 2009; I issued MEL 33-01a for Cockpit lighting; due to a portion of the lights not reacting to the Dimming switch. A few days later; a Pilot flying from ZZZ called and said he thought the MEL should be 33-23a; which is the Master Dim System. At his request the MEL was reclassified. The Captain believed it was incorrect so it was reclassified per his request. Interpretation of which MEL applied was the issue. When the Captain called to reclassify the MEL; it was determined that by doing so; it was a 'Drop Dead' MEL due to time limits from the date of discovery. Clarification of the intent of the MEL (is needed). Do they mean any part of the system or the complete (Master) Dim Test function?

Data retrieved from NASA's ASRS site as of April 2012 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	863172
Time
Date	200911
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Dawn
Aircraft 1
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Cockpit Lighting
Person 1
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural MEL

A line mechanic reports the need to clarify the intent of the MEL language in MEL chapter 33-23a; regarding the cockpit lighting master dim system; compared to MEL 33-01a. A portion of the cockpit lights were not reacting to the dimming switch and confusion arose as to which MEL applied.