Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
What sort of test equipment do you have? Multimeter, test light?
Can you test for voltage at any of the fuses in the fuse box? What we need to do is figure out where the voltage loss occurs. Try your test light on the main power lead into the fuse box first and then we'll go from there. The main power lead to the alternator is a good place to test as well. It should have solid battery voltage at the main (usually red) wire all the time.
If you have no power to anything at all it's probably a blown megafuse or a bad battery connection.
Each item you listed, lights, horn, etc, all have their own circuit. For them all to be out at once then it has to be somewhere in the main common power feed- battery, battery connection, or one or both of the main megafuses.
Was the battery jumped or replaced recently?
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