Voyager 2 has been going strong for over 40 years, but it’s beginning to show signs of its age. NASA is reporting that a fault has caused the spacecraft to lock itself down in safe mode, as engineers work to get it back up and running again.

According to NASA, Voyager 2 failed to perform a scheduled maneuver on Saturday January 25. The craft was due to rotate a full 360 degrees to calibrate its magnetic field instrument, but for some reason the action was delayed. That in turn meant that two particularly power-hungry systems were left running at the same time, which overdrew the available power supply.

Because a mechanic can’t exactly be sent 11.5 billion miles (18.5 billion km) to look at it, Voyager 2 is designed to automatically react to these situations by going into a low power mode, preventing any damage. Engineers back at NASA HQ can then communicate with the craft to try to troubleshoot the problem.

As of January 28, the team managed to turn off one of those high-power systems, allowing some scientific instruments to be switched back on. Engineers are currently analyzing data to figure out the status of the rest of the systems, to work out how to turn off the second one and return the craft to normal operations.

The whole process is slow going, though, thanks to the sheer distance involved. Since Voyager 2 and its twin are out in interstellar space, it takes communications from NASA about 17 hours to reach it, and then another 17 to get a reply.

Hopefully, though, the historic spacecraft is up and running again soon, beaming back data from the fringes of the solar system for years to come.

Source: NASA JPL