Narrative:

After repairing a B737-300's L-1 (left) window for an overheat light issue and returning the aircraft to service; the next outbound flight crew at pushback stated that the L-1 window overheat light came on again. I verified that it had again failed and proceeded at the gate to swap the L-1 window to the spare sensor [electrical] posts. During this act of maintenance; I had dropped a screwdriver behind the instrument panel. In order to gain access to the area where it fell; I was required to remove the P1-2 [forward] panel.with the window now working normally; satisfied that it would cause no more problems; along with retrieving the screwdriver; I proceeded to install all of the removed components. I had notified maintenance control that I was confident that the window was repaired and that the aircraft could be ready in an hour to an hour and a half. No more than 15 minutes later a flight crew shows up at the aircraft stating that the aircraft was due out in an additional 15 minutes. With this additional pressure I started to make mistakes. First; while installing the glare shield; I thought that I had installed the instrument background lighting connectors; however as the gate return stated; I had not.secondly; I was very cautious while reinstalling all the cannon plugs on the P1-2 panel; inspecting the marker tags two or three times before installing them on their related indicators. As you can see by the second gate return; I had misconnected the N2 indicators. All of these actions on my part were done according to the appropriate maintenance manual and/or standard wiring practices. Now as far as some of the existing human factors playing on all of this; they are as follows:fatigue [was] the number one contributing factor. I had not had any good rest prior to the start of my first overtime shift which was then extended to work on aircraft.second factor was stress. When I had informed maintenance control that the aircraft could be ready in an hour to hour and a half and then the flight crew shows up in 15 minutes; I had put pressure on myself to complete the repairs so that a new on-time departure could be made.third and finally; was complacency. I was certain that I could complete the repairs with no mistakes; I found that this was not going to happen. I can't express the way this made me feel. I am normally not this complacent with any part of my life; especially here on aircraft. The safety of our customer is our number one priority.

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Original NASA ASRS Text

Title: A Line Mechanic reported a chain of events that contributed to his not properly connecting both engine N2 indicators while reinstalling the P1-2 forward instrument panels that resulted in a gate return for a B737-300 aircraft. Fatigue from an extended overtime shift; complacency; stress and distraction from concerns about meeting departure schedules were noted.

Narrative: After repairing a B737-300's L-1 (left) window for an overheat light issue and returning the aircraft to service; the next outbound flight crew at pushback stated that the L-1 window overheat light came on again. I verified that it had again failed and proceeded at the gate to swap the L-1 window to the spare sensor [electrical] posts. During this act of maintenance; I had dropped a screwdriver behind the instrument panel. In order to gain access to the area where it fell; I was required to remove the P1-2 [forward] panel.With the window now working normally; satisfied that it would cause no more problems; along with retrieving the screwdriver; I proceeded to install all of the removed components. I had notified Maintenance Control that I was confident that the window was repaired and that the aircraft could be ready in an hour to an hour and a half. No more than 15 minutes later a flight crew shows up at the aircraft stating that the aircraft was due out in an additional 15 minutes. With this additional pressure I started to make mistakes. First; while installing the glare shield; I thought that I had installed the instrument background lighting connectors; however as the gate return stated; I had not.Secondly; I was very cautious while reinstalling all the cannon plugs on the P1-2 panel; inspecting the marker tags two or three times before installing them on their related indicators. As you can see by the second gate return; I had misconnected the N2 indicators. All of these actions on my part were done according to the appropriate Maintenance manual and/or standard wiring practices. Now as far as some of the existing human factors playing on all of this; they are as follows:Fatigue [was] the number one contributing factor. I had not had any good rest prior to the start of my first overtime shift which was then extended to work on aircraft.Second factor was stress. When I had informed Maintenance Control that the aircraft could be ready in an hour to hour and a half and then the flight crew shows up in 15 minutes; I had put pressure on myself to complete the repairs so that a new on-time departure could be made.Third and finally; was complacency. I was certain that I could complete the repairs with no mistakes; I found that this was not going to happen. I can't express the way this made me feel. I am normally not this complacent with any part of my life; especially here on aircraft. The safety of our customer is our number one priority.

Data retrieved from NASA's ASRS site as of April 2012 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.