EMB ERJ 145 ER/LR
Maintenance Powerplant; Maintenance Airframe
Distraction; Fatigue; Time Pressure
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural MEL / CDL
General None Reported / Taken
Company Policy; Environment - Non Weather Related; Aircraft; Human Factors; MEL; Procedure
I went on road trip to ZZZ to complete a lightning strike inspection on Aircraft X. My colleague and I left our base around [evening] on [Day X]. When we got to ZZZ; we started the inspection and replaced the damaged parts as required. We finished the task on [Day X+1] around [nightfall]. We were getting ready to board on the plane to get back to our base when the flight crew alerted us about an active message on EICAS. We troubleshot the message according to fault isolation manual and found the cause but due to time we have to defer the maintenance. We first had to comply with maintenance procedures which consisted of inserting locking pin on lower and upper thrust reverser door and then on ICU (Internal Compensation Unit) located inside tail cone. Without being aware I inserted the pin on the wrong ICU. We deferred the RH thrust reverser and the pin should normally being inserted on RH ICU instead of LH.When the incident happened I was on clock for 31 hours without break.  I clock in at my base at [early afternoon] on [Day X] and left for road trip around [the evening]. I got to ZZZ [later that night] and worked on airplane from that time [into the night] on [Day X+1]. At the time we have to complete that deferral; I was very tired due to lack of rest. Management did not give me the opportunity to take break. I was hungry and tired. I believe the elements I cited below may have affected my ability to perform my job adequately   In others to avoid such incidents in future; I suggest that management give mandatory rest times to mechanics after completion of certain works hours; and also put enough mechanics on tasks to release heavy work load.
Technician reported that fatigue contributed to not following MEL procedures and he locked out the wrong thrust reverser in error.