A line mechanic reported that he removed and replaced (right/right) a B757-200 anti-collision light ...

Narrative:

Pilot reported nose landing light switch remains 'on' with switch in the 'off' position; after cycling the switch 3 times the light turned 'off'.I removed and replaced the anti-collision light control panel switching unit on the P-5 overhead panel. The nose landing light switch is on this panel. This occurred during a one hour ground time between flights. I ordered the switching unit with the manufactures part number (mpn) that was on the part that I removed from the B757-200. I installed the new switching unit mpn and performed an operational check per the maintenance manual. All lights on the anti-collision light control panel unit operated normally.when returning to enter paperwork and verify correct part number in the illustrated parts catalog (ipc); I realized that the part was not effective for that B757-200. This was discovered after the aircraft had dispatched. I immediately contacted the maintenance control; and my supervisor to let them know what had occurred and to resolve the problem.the correct manufactures part number (mpn) was set up by maintenance control to be installed on the aircraft.

Original NASA ASRS Text

Title: A Line Mechanic reported that he Removed and Replaced (R/R) a B757-200 Anti-Collision light Control panel Switching unit on the P-5 Cockpit overhead panel. The Operational Check passed but Mechanic realized later he had installed a Switching Unit that was not effective for the aircraft.

Narrative: Pilot reported Nose landing light switch remains 'On' with switch in the 'Off' position; after cycling the switch 3 times the light turned 'Off'.I Removed and replaced the Anti-Collision light control panel Switching unit on the P-5 overhead panel. The Nose landing light switch is on this panel. This occurred during a one hour ground time between flights. I ordered the Switching unit with the Manufactures Part Number (MPN) that was on the part that I removed from the B757-200. I installed the new Switching unit MPN and performed an operational check per the Maintenance Manual. All lights on the Anti-Collision light control panel unit operated normally.When returning to enter paperwork and verify correct Part Number in the Illustrated Parts Catalog (IPC); I realized that the part was not effective for that B757-200. This was discovered after the aircraft had dispatched. I immediately contacted the Maintenance Control; and my Supervisor to let them know what had occurred and to resolve the problem.The correct Manufactures Part Number (MPN) was set up by Maintenance Control to be installed on the aircraft.

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	865922
Time
Date	200912
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Night
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Landing Light
Person 1
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Experience	Maintenance Technician 12
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural FAR Deviation - Procedural Published Material / Policy

A line mechanic reported that he removed and replaced (right/right) a B757-200 anti-collision light control panel switching unit on the P-5 cockpit overhead panel. The operational check passed but mechanic realized later he had installed a switching unit that was not effective for the aircraft.