Toyota Repair: MR2 Warning Lights, radiator fan, 3sge

Question
Hello Ted, My sons 1991 SW20 MR2 3SGE has been sitting around for a few months and when we went to start it the battery was dead. So charged it and it started and ran fine, unfortunately we have 3 warning lights staying on. Battery/ Exhaust temp / Radiator fan. I have since replaced the battery as it wouldnt hold a charge. Lights still remain on. It hasnt gone far as I dont wont him getting stranded anywhere, if it falls. Any ideas? Thanks

Answer
The alternator output should be tested and replaced if necessary, if you have a voltmeter available connect it across the terminals of the battery with the engine running and all the lights and accessories turned on, the voltage should read at least 13.2 volts, if it's lower the alternator should be replaced, it is not charging the battery.