Rover Team Working to Diagnose Electrical Issue
Mars Science Laboratory Mission Status Report
Science observations by NASA's Mars rover Curiosity have been suspended for a few days while engineers run tests to check possible causes of a voltage change detected on Nov. 17.
"The vehicle is safe and stable, fully capable of operating in its present condition, but we are taking the precaution of investigating what may be a soft short," said Mars Science Laboratory Project Manager Jim Erickson at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
A "soft" short is a leak through something that's partially conductive of electricity, rather than a hard short such as one electrical wire contacting another.
The team detected a change in the voltage difference between the chassis and the 32-volt power bus that distributes electricity to systems throughout the rover. Data indicating the change were received on Sunday, during Curiosity's 456th Martian day. The level had been about 11 volts since landing day, and is now about 4 volts. The rover's electrical system is designed with the flexibility to work properly throughout that range and more -- a design feature called "floating bus."
http://www.jpl.nasa.gov/news/news.php?release=2013-337