A B737-700 was being troubleshot for a thrust reverser report. Circuit breakers were not pulled.

Attributes
ACN	669103
Time
Date	200508
Place
Locale Reference	airport : zzz.airport
State Reference	US
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
ASRS Report	669103
Person 2
Affiliation	company : air carrier
Function	maintenance : lead technician
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper maintenance maintenance problem : improper documentation non adherence : far non adherence : published procedure
Independent Detector	other other : 2
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	contributing factor : work cards performance deficiency : testing performance deficiency : fault isolation performance deficiency : logbook entry performance deficiency : non compliance with legal requirements performance deficiency : installation performance deficiency : training
Supplementary
Problem Areas	Maintenance Human Performance Chart Or Publication Aircraft
Primary Problem	Maintenance Human Performance

Narrative:

Aircraft X arrived for overnight work to be performed. #1 thrust reverser on MEL. I troubleshot system by unpinning thrust reverser and cutting safety wire on handle so I could slide the sleeve back in order to reset engine assembly unit. When the bite was completed and parts were not available; I rewired reverser handle and pinned thrust reverser. I did not pull any breakers for the system. I looked at the MEL book and did not see on the maintenance procedures to pull any breakers. I saw on the other dash number aircraft to pull breakers but not on the new gen which is why none were pulled. I've reviewed the MEL procedure since this incident occurred and am aware that pulling of the breakers are in the maintenance manual procedures.

Original NASA ASRS Text

Title: A B737-700 WAS BEING TROUBLESHOT FOR A THRUST REVERSER RPT. CIRCUIT BREAKERS WERE NOT PULLED.

Narrative: ACFT X ARRIVED FOR OVERNIGHT WORK TO BE PERFORMED. #1 THRUST REVERSER ON MEL. I TROUBLESHOT SYS BY UNPINNING THRUST REVERSER AND CUTTING SAFETY WIRE ON HANDLE SO I COULD SLIDE THE SLEEVE BACK IN ORDER TO RESET ENG ASSEMBLY UNIT. WHEN THE BITE WAS COMPLETED AND PARTS WERE NOT AVAILABLE; I REWIRED REVERSER HANDLE AND PINNED THRUST REVERSER. I DID NOT PULL ANY BREAKERS FOR THE SYS. I LOOKED AT THE MEL BOOK AND DID NOT SEE ON THE MAINT PROCS TO PULL ANY BREAKERS. I SAW ON THE OTHER DASH NUMBER ACFT TO PULL BREAKERS BUT NOT ON THE NEW GEN WHICH IS WHY NONE WERE PULLED. I'VE REVIEWED THE MEL PROC SINCE THIS INCIDENT OCCURRED AND AM AWARE THAT PULLING OF THE BREAKERS ARE IN THE MAINT MANUAL PROCS.

Data retrieved from NASA's ASRS site as of January 2009 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.