A B737-300 was dispatched with the incorrect standby power module installed.

Attributes
ACN	637887
Time
Date	200411
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-400
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
ASRS Report	637887
Person 2
Affiliation	company : air carrier
Function	maintenance : lead technician
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : improper maintenance non adherence : published procedure non adherence : far
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	contributing factor : schedule pressure performance deficiency : installation performance deficiency : logbook entry performance deficiency : non compliance with legal requirements
Supplementary
Problem Areas	Chart Or Publication Aircraft Maintenance Human Performance
Primary Problem	Maintenance Human Performance

Narrative:

On nov/thu/04 at approximately XA30, the standby power module required changing. I removed, replaced. And operations checked the new standby power module per the maintenance manual. I checked and saw that serial number XXX was effective for that part. After learning about the wrong part being installed, I later checked and apparently entered X instead of Y on the tail # which gave me effectivity readings improperly.

Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED WITH THE INCORRECT STANDBY PWR MODULE INSTALLED.

Narrative: ON NOV/THU/04 AT APPROX XA30, THE STANDBY PWR MODULE REQUIRED CHANGING. I REMOVED, REPLACED. AND OPS CHKED THE NEW STANDBY PWR MODULE PER THE MAINT MANUAL. I CHKED AND SAW THAT SERIAL NUMBER XXX WAS EFFECTIVE FOR THAT PART. AFTER LEARNING ABOUT THE WRONG PART BEING INSTALLED, I LATER CHKED AND APPARENTLY ENTERED X INSTEAD OF Y ON THE TAIL # WHICH GAVE ME EFFECTIVITY READINGS IMPROPERLY.

Data retrieved from NASA's ASRS site as of July 2007 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.