The FCC has closed a two-year investigation into a crash of MetroPCS’ wireless network in California that examined whether the company violated rules requiring operators to report network outages to the FCC.

The FCC did not say it found MetroPCS in violation of the rules, but the operator has agreed to pay a $45,000 “voluntary contribution” to the U.S. Treasury, set up a training program to teach employees about network outage reporting regulations and submit regular reports on the program to the FCC.

“In express reliance on the covenants and representations in this Consent Decree and to avoid further expenditure of public resources, the Bureau agrees to terminate the investigation,” the FCC said Thursday. “In consideration for the termination of said investigation, MetroPCS agrees to the terms, conditions and procedures contained herein.”

Concerns about MetroPCS’ network outage reporting first came to the attention of the FCC in 2008, when the Public Safety and Homeland Security Bureau referred MetroPCS to the Enforcement Bureau for potential violations of the network outage reporting requirements.

On April 8, 2009, the agency’s Enforcement Bureau began an investigation into the issue and asked MetroPCS to submit sworn testimony about how it reported network crashes.

Wireless operators are required to notify the FCC of network outages lasting 30 minutes or more within two hours of the incident. Operators must submit an additional report on major outages within three days, with a follow-up report due 30 days later.

The regulations cover an outage at a mobile switching center; a crash that could affect at least 900,000 user minutes of either telephony or paging, or 1,350 DS3 minutes; an outage that could affect any special offices, facilities or 911 centers.