Just bought a used 09 Scion xb. Iʻve had it for a week. The battery warning light comes on then about 30 minutes later (while driving) reversing into a parking stall,the power steering goes out. Right after that I put in a brand new battery, the power steering come back but the battery light is going on then off for a little while and back on. Plus now the idle is really low like its going to die off. Im thinking I need a new alternator.