Narrative:

An aircraft arrived for regular overnight routine maintenance. It had a deferred item for the left engine bleed off light inoperative but tests good. It was previously troubleshot to an open wire between P-50 panel and P-61 panel. I spliced in a new section of wire per maintenance coordinator, but was doubtful if this would be a good fix because the aircraft was pretty new (less than 5 yrs old). I used raychem type environmental splices, which have a plastic sheath which is slipped over the splice and heat shrunk around it. My suspicions proved correct and the light was inoperative. I started troubleshooting system myself, which consisted of swapping logic cards from right side to left side to see if problem followed. This involved going from flight deck to east&east compartment a number of times to kill power, insert card, turn on power, test system, turn off power, swap cards back, etc. I also had 3 panels taken off in flight deck. During all this, I lost track of time and then the crew arrived. In my haste to get aircraft back together, I forgot that I had not shrunk-wrapped the sheaths on the splices.

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Original NASA ASRS Text

Title: A B767-300 WAS DISPATCHED IN NON COMPLIANCE WITH AN INCOMPLETE ELECTRICAL WIRE SPLICE REPAIR ACCOMPLISHED WITHOUT HEAT SHRINK INSULATION APPLIED.

Narrative: AN ACFT ARRIVED FOR REGULAR OVERNIGHT ROUTINE MAINT. IT HAD A DEFERRED ITEM FOR THE L ENG BLEED OFF LIGHT INOP BUT TESTS GOOD. IT WAS PREVIOUSLY TROUBLESHOT TO AN OPEN WIRE BTWN P-50 PANEL AND P-61 PANEL. I SPLICED IN A NEW SECTION OF WIRE PER MAINT COORDINATOR, BUT WAS DOUBTFUL IF THIS WOULD BE A GOOD FIX BECAUSE THE ACFT WAS PRETTY NEW (LESS THAN 5 YRS OLD). I USED RAYCHEM TYPE ENVIRONMENTAL SPLICES, WHICH HAVE A PLASTIC SHEATH WHICH IS SLIPPED OVER THE SPLICE AND HEAT SHRUNK AROUND IT. MY SUSPICIONS PROVED CORRECT AND THE LIGHT WAS INOP. I STARTED TROUBLESHOOTING SYS MYSELF, WHICH CONSISTED OF SWAPPING LOGIC CARDS FROM R SIDE TO L SIDE TO SEE IF PROB FOLLOWED. THIS INVOLVED GOING FROM FLT DECK TO E&E COMPARTMENT A NUMBER OF TIMES TO KILL PWR, INSERT CARD, TURN ON PWR, TEST SYS, TURN OFF PWR, SWAP CARDS BACK, ETC. I ALSO HAD 3 PANELS TAKEN OFF IN FLT DECK. DURING ALL THIS, I LOST TRACK OF TIME AND THEN THE CREW ARRIVED. IN MY HASTE TO GET ACFT BACK TOGETHER, I FORGOT THAT I HAD NOT SHRUNK-WRAPPED THE SHEATHS ON THE SPLICES.

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.