B737-700
Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Distraction; Situational Awareness; Time Pressure
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors; MEL
The aircraft was at the gate with a #2 Stall Warning [System] that would not test. I had another aircraft waiting for maintenance and had received the request while working on a different aircraft. I arrived while boarding was in process and performed a BITE Test of the #2 Stall Management Yaw Damper and found no faults. I contacted Maintenance Control to defer the #2 Stall Warning System. There was a bit of confusion between myself and Maintenance Control on the MEL for #1 or #2 Stall Warning but we worked through that. I placed the aircraft on MEL; pulled and collared the Stick Shaker Right Circuit Breaker Auto Stow Circuit Breaker but missed the [step to collar the] Flight Controls Auto Speed Brake Circuit Breaker. The pressure; time constraints and distractions caught up to me on this one. Perhaps a list of circuit breakers to be pulled; in a list style with all the circuit breakers in one place instead of different paragraphs.
A Maintenance Technician missed a step in the MEL deactivation procedure and neglected to open and collar the Auto Speedbrake Circuit Breaker. He sighted time pressure and distractions as contributing factors.