science

The problem was that Voyager sent junk data back to us due to a memory fault. It was still responsive to receive updates from Earth and to pings.

Pinging Voyager 1 takes about 2 days, so testing updates is naturally quite slow.

Im guessing it could still listen just not talk back

Edit read the article

Although the radio signal from the spacecraft had never ceased its connection to ground control operators on Earth during the computer problem, that signal had not carried any usable data since

It's simple rocket science

This Satelite must offer option to install software updates over the air, so they modified software and slowly uploaded it to the satelite.