Posted Jan 3rd by Prudence the owner of a Ford Focus
Answers from the Automotive Experts
I would have the battery checked. Because the radio only needs a small amount of current, it may come on when the battery is low. However, it takes much more to crank the starter. Most likely your battery needs a charge or it's time for a new one.
〉 Answered on Jan 3rd, 2008 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines