Lost electrical power. no lights and car wont start. on 1991 Chevrolet Corsica

car worked fine, tried to start and lost all power electricly. checked fuses everything good. no sounds at all when it lost power. lights radio dont work anymore. cleaned battery reconnected still no power

Asked by for the 1991 Chevrolet Corsica
Check the battery connections are clean tight and secure. Check the battery voltage at rest it should be 12.6 volts engine running it should read 14.7 volts approximately if the alternator is charging correctly. Try "jump starting" the car using jumper cables and see if the lights now come on and or the car starts, if so charge and test the battery, check the charging system and check for battery draw.