Narrative:

While at the gate; maintenance was working on the hydraulic system to defer the auto brakes and anti skid. They had told us not to turn on the electric hydraulic pumps or packs. Eventually we received a new [maintenance release] over ACARS saying they were done with the maintenance procedure and releasing the flight. We then prepared the aircraft for pushback which included turning the hydraulic pumps and packs on. As we were doing the checklist a mechanic began waving his arms and shouting outside my window to turn the packs off which I did. I requested a maintenance supervisor report to the cockpit and learned that the mrd should not have been issued and that they were still working on the hydraulic system. There were no injuries.

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Original NASA ASRS Text

Title: B737NG flight crew reported they prematurely began to prepare for departure; including turning on packs and hydraulic pumps; after they were erroneously notified via ACARS that maintenance had completed their work.

Narrative: While at the gate; Maintenance was working on the hydraulic system to defer the auto brakes and anti skid. They had told us not to turn on the electric hydraulic pumps or packs. Eventually we received a new [maintenance release] over ACARS saying they were done with the maintenance procedure and releasing the flight. We then prepared the aircraft for pushback which included turning the hydraulic pumps and packs on. As we were doing the checklist a mechanic began waving his arms and shouting outside my window to turn the packs off which I did. I requested a maintenance supervisor report to the cockpit and learned that the MRD should not have been issued and that they were still working on the hydraulic system. There were no injuries.

Data retrieved from NASA's ASRS site 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.