April 15, 2003
Prelaunch at Kennedy Space Center

In the Payload Hazardous Servicing Facility, the lander petals of the Mars Exploration Rover 2 (MER-2) have been reopened and its solar panels deployed to allow technicians access to the spacecraft to remove one of its circuit boards. A concern arose during prelaunch testing regarding how the spacecraft interprets signals sent from its main computer to peripherals in the cruise stage, lander and small deep space transponder. The MER Mission consists of two identical rovers set to launch in June 2003. The problem will be fixed on both rovers.