A320
Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Fatigue; Situational Awareness; Time Pressure
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural MEL / CDL
General Maintenance Action
Human Factors; MEL
Early morning; received a gate call for [Air Conditioning] Pack Regulator fault. Tried to perform an Operational Check to try to reset the system; but could not get the system to reset. Contacted Maintenance Control and both of us agreed to place Pack-1 on MEL 21-51-01C for a Pack Regulator fault. We both missed one step of the MEL where it requires to also apply MEL 21-52-01D. The aircraft flew one flight before MEL 21-52-01D was applied. Lack of Communication between Myself and Maintenance Controller. We both agreed on which MEL to apply but failed to apply second MEL called for. This event happened at the end of my shift; so fatigue may have also been a factor. This event could have been prevented by being more familiar with MEL procedures and reviewing the MEL once applied.
A Line Aircraft Maintenance Technician (AMT) cites a lack of communication between himself and a Maintenance Controller as the primary cause of their releasing an A320 aircraft with an incomplete MEL deferral of Air Conditioning Pack-1 for a Pack Regulator fault.