The aging power-challenged Voyager 1 spacecraft suffered another glitch 2 weeks ago – it stopped calling home on its regular channel. Here is the sequence of events that transpired -
Oct 16 – Command sent to turn on a heater
Oct 18 – X-band signal lost; team surmised that the power-overload triggered the fault protection system and Voyager switched to a low-rate low-power X-band mode
Oct 18 – DSN looked for lower-rate X-band signal and found it
(contd)
Voyager 2 shuts down science experiment as power stores dwindle.
From CNN: "Mission engineers sent a command to shutter the Voyager 2’s Plasma Science, or PLS, experiment — which was used to observe solar winds — on September 26 using the Deep Space Network, a series of massive radio antennae that can beam information billions of miles through space. It took 19 hours for the message to reach Voyager 2, and a return signal was received 19 hours later."
NASA Voyager update - on Sept 26, one more instrument aboard Voyager 2 was turned off to conserve power - the plasma science instrument.
Over the 46 years since launch, Voyager instruments have gradually been shut off as power levels have declined by over 50%. Now just 4 science instruments remain active to study the region outside our heliosphere. See graphic below.
Note that the plasma science instrument on Voyager 1 failed and was turned off in 2007.