B737-900
Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Confusion; Situational Awareness; Troubleshooting; Workload
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Maintenance
Aircraft Aircraft Damaged; General Flight Cancelled / Delayed; General Maintenance Action
Procedure; Aircraft
During thrust reverser cycling #2 eng inadvertently started causing over temp to 821.5 to 28 seconds. As per MM 71-00-00-800-804-f00; [it] will require boroscope due to temp going into area C of chart. I did not notice that the APU bleed was left on and I did not pull ignition circuit breakers. [I] had 2 techs clearing around engine.
Inspector reported omitting steps during a borescope for engine overtemperature.