Narrative:

On feb/tue/03, xyz was assigned to perform eo (engineering order, software upgrade) on aircraft X. While performing engineering order they were required to replace the ACARS mu (management unit). The new management unit could not be installed due aircraft being keyed incorrectly. Old management unit was reinstalled, engineering order was deferred until aircraft was keyed correctly. On dec/sat/02, aircraft X's engineering order was accomplished by yzz. The aircraft X should have been correctly keyed then. Xyz attempted to change unit and found aircraft was keyed incorrectly. On feb/fri/03, management unit was removed from aircraft X and sent to avionics shop. I performed software update (engineering service order revision ag) also found cold solder joint on power supply connector (internal connector). I made all repairs. I did not have to re-key this management unit. It installed normally on my shop test set. I did not look at keying on the main connector because the request came after I had returned unit to service. This could have been confirmed if the request was on the serviceable parts tag.

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Original NASA ASRS Text

Title: AN AVIONICS SHOP TECHNICIAN RPTS UPDATED ACARS MGMT UNITS COULD NOT BE INSTALLED DUE TO INCORRECT ACCOMPLISHMENT OF AN ENGINEERING ORDER TO CHANGE THE MOUNTING RACK KEYWAY.

Narrative: ON FEB/TUE/03, XYZ WAS ASSIGNED TO PERFORM EO (ENGINEERING ORDER, SOFTWARE UPGRADE) ON ACFT X. WHILE PERFORMING ENGINEERING ORDER THEY WERE REQUIRED TO REPLACE THE ACARS MU (MGMNT UNIT). THE NEW MGMNT UNIT COULD NOT BE INSTALLED DUE ACFT BEING KEYED INCORRECTLY. OLD MGMNT UNIT WAS REINSTALLED, ENGINEERING ORDER WAS DEFERRED UNTIL ACFT WAS KEYED CORRECTLY. ON DEC/SAT/02, ACFT X'S ENGINEERING ORDER WAS ACCOMPLISHED BY YZZ. THE ACFT X SHOULD HAVE BEEN CORRECTLY KEYED THEN. XYZ ATTEMPTED TO CHANGE UNIT AND FOUND ACFT WAS KEYED INCORRECTLY. ON FEB/FRI/03, MGMNT UNIT WAS REMOVED FROM ACFT X AND SENT TO AVIONICS SHOP. I PERFORMED SOFTWARE UPDATE (ENGINEERING SVC ORDER REVISION AG) ALSO FOUND COLD SOLDER JOINT ON PWR SUPPLY CONNECTOR (INTERNAL CONNECTOR). I MADE ALL REPAIRS. I DID NOT HAVE TO RE-KEY THIS MGMNT UNIT. IT INSTALLED NORMALLY ON MY SHOP TEST SET. I DID NOT LOOK AT KEYING ON THE MAIN CONNECTOR BECAUSE THE REQUEST CAME AFTER I HAD RETURNED UNIT TO SVC. THIS COULD HAVE BEEN CONFIRMED IF THE REQUEST WAS ON THE SERVICEABLE PARTS TAG.

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.