Narrative:

Aircraft X was at the gate after remain overnight at ZZZ. Prior to pushback for the first flight of the day, the captain called maintenance lead via radio and reported electrical fault light illuminated. I was dispatched to the aircraft and confirmed the problem. I conducted an operations check of the standby power control unit per the task card and confirmed the battery charged positive so I could MEL the discrepancy and dispatch the aircraft. Passenger were already loaded on the aircraft. I returned to the line to contact maintenance control and complete the paperwork. The lead informed me the aircraft had a similar discrepancy back in august. At that time the standby power control unit had been reset and that cured the problem. I returned to the aircraft and individually pulled each circuit breaker on the standby power control unit in hopes of resetting it. I inadvertently secured aircraft power. The APU was restarted and power restored. The electrical fault light remained on, so I returned to line maintenance to complete the MEL paperwork. While at the line, the captain radioed and stated the first officer's speed and altitude flags illuminated on his pfd. I called technical services who informed me the speed and altitude information came from the adiru. I returned to the aircraft and pulled and reset the #2 adiru AC, exc, and dc circuit breakers. I felt the #2 adiru failed to power up properly after the last power down. Immediately after the #2 adiru circuit breakers were reset, the first officer's pfd indications were restored to normal. I waited for #2 inertial reference unit to align and the map display returned to normal also on the first officer's side. I then cleared the logbook entry made by the captain. I performed no maintenance manual or task card procedure, and feel the first officer pfd discrepancy was an operational issue. Had the pilots turned off then realigned the #2 IRU with the overhead panel switch, this discrepancy would have cleared. After I completed the paperwork, the aircraft was dispatched. I was informed by my line maintenance manager that an initial notification of apparent violation had been initiated. Self disclosure #xx-xxxxx that I had failed to downgrade the lower WX minimum performance status of the aircraft. I filed an as soon as possible report within 24 hours (reference XXXX-xx. I didn't feel the CAT status had been compromised since I did not touch and lower WX minimum performance sensitive line replace units or components. I did not want to completely power down the aircraft again with passenger on board, so utilized the circuit breakers to reboot the adiru, which worked.

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Original NASA ASRS Text

Title: A B737-700 PRIOR TO DEP RPTED FO'S PFD HAD SPD AND ALT FLAGS. TECHNICIAN REALIGNED THE #2 IRU.

Narrative: ACFT X WAS AT THE GATE AFTER REMAIN OVERNIGHT AT ZZZ. PRIOR TO PUSHBACK FOR THE FIRST FLT OF THE DAY, THE CAPT CALLED MAINT LEAD VIA RADIO AND RPTED ELECTRICAL FAULT LIGHT ILLUMINATED. I WAS DISPATCHED TO THE ACFT AND CONFIRMED THE PROB. I CONDUCTED AN OPS CHK OF THE STANDBY PWR CTL UNIT PER THE TASK CARD AND CONFIRMED THE BATTERY CHARGED POSITIVE SO I COULD MEL THE DISCREPANCY AND DISPATCH THE ACFT. PAX WERE ALREADY LOADED ON THE ACFT. I RETURNED TO THE LINE TO CONTACT MAINT CTL AND COMPLETE THE PAPERWORK. THE LEAD INFORMED ME THE ACFT HAD A SIMILAR DISCREPANCY BACK IN AUGUST. AT THAT TIME THE STANDBY PWR CTL UNIT HAD BEEN RESET AND THAT CURED THE PROB. I RETURNED TO THE ACFT AND INDIVIDUALLY PULLED EACH CIRCUIT BREAKER ON THE STANDBY PWR CTL UNIT IN HOPES OF RESETTING IT. I INADVERTENTLY SECURED ACFT PWR. THE APU WAS RESTARTED AND PWR RESTORED. THE ELECTRICAL FAULT LIGHT REMAINED ON, SO I RETURNED TO LINE MAINT TO COMPLETE THE MEL PAPERWORK. WHILE AT THE LINE, THE CAPT RADIOED AND STATED THE FO'S SPD AND ALT FLAGS ILLUMINATED ON HIS PFD. I CALLED TECHNICAL SVCS WHO INFORMED ME THE SPD AND ALT INFO CAME FROM THE ADIRU. I RETURNED TO THE ACFT AND PULLED AND RESET THE #2 ADIRU AC, EXC, AND DC CIRCUIT BREAKERS. I FELT THE #2 ADIRU FAILED TO PWR UP PROPERLY AFTER THE LAST PWR DOWN. IMMEDIATELY AFTER THE #2 ADIRU CIRCUIT BREAKERS WERE RESET, THE FO'S PFD INDICATIONS WERE RESTORED TO NORMAL. I WAITED FOR #2 INERTIAL REF UNIT TO ALIGN AND THE MAP DISPLAY RETURNED TO NORMAL ALSO ON THE FO'S SIDE. I THEN CLRED THE LOGBOOK ENTRY MADE BY THE CAPT. I PERFORMED NO MAINT MANUAL OR TASK CARD PROC, AND FEEL THE FO PFD DISCREPANCY WAS AN OPERATIONAL ISSUE. HAD THE PLTS TURNED OFF THEN REALIGNED THE #2 IRU WITH THE OVERHEAD PANEL SWITCH, THIS DISCREPANCY WOULD HAVE CLRED. AFTER I COMPLETED THE PAPERWORK, THE ACFT WAS DISPATCHED. I WAS INFORMED BY MY LINE MAINT MGR THAT AN INITIAL NOTIFICATION OF APPARENT VIOLATION HAD BEEN INITIATED. SELF DISCLOSURE #XX-XXXXX THAT I HAD FAILED TO DOWNGRADE THE LOWER WX MINIMUM PERFORMANCE STATUS OF THE ACFT. I FILED AN ASAP RPT WITHIN 24 HRS (REF XXXX-XX. I DIDN'T FEEL THE CAT STATUS HAD BEEN COMPROMISED SINCE I DID NOT TOUCH AND LOWER WX MINIMUM PERFORMANCE SENSITIVE LINE REPLACE UNITS OR COMPONENTS. I DID NOT WANT TO COMPLETELY PWR DOWN THE ACFT AGAIN WITH PAX ON BOARD, SO UTILIZED THE CIRCUIT BREAKERS TO REBOOT THE ADIRU, WHICH WORKED.

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.