Impressively, the spacecraft continues to send data back to Earth, but recently its telemetry data has been invalid; according to NASA, the data simply doesn’t match up with whatever Voyager 1’s true position and conditions might be.
The Voyager team continues to scrutinize the weird attitude articulation and control (AACS) data; they’re not sure whether the problem comes directly from that system or another part of the spacecraft.
Data from the probes revealed a previously unknown phenomenon of the interstellar medium, and Voyager 1 recently detected oscillations in the plasma of deep space.