92 Sonoma worked fine day before . Turn key to start and loose all power, everything goes dead? Battery is fully charged, tested with hydrometer.
This could be numerous things. I would start with battery still. Put it on a load test. This might reveal loose connections on battery or bad battery. Most auto places now will test your battery for free. The hydrometer is a good test to check specific gravity of acid in battery, but not a test for any bad connections. Sometimes if you leave the headlights on and try starting you can reveal a bad connection.
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