I fixed 2 subarus like that, It was the instrument cluster went bad . they heat and contract a lot and some of the solider connects would lose contact... and when I took them out you could see burn/ hot spots where the connections went bad. A couple I fixed just by re heating the solider, Its called wetting the joint again...and they made contact again
and as far as the battery just put a volt meter on the battery and rev it up. It should be showing 14.5 and up on the volts going to the battery when running. If it does chances are its time for a new battery
Realist - Everybody in America is soft, and hates conflict. The cure for this, both in politics and social life, is the same -- hardihood. Give them raw truth.