headlights and radio stopped working

1980 CHEVROLET BLAZER
15,600 MILES
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BARBI_KERSEY
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I have a 1980 chevy blazer and the headlights and radio stopped working at the same time. we have checked all fuses and they are ok. also there is an unknown drain on the battery and if we don't unhook the battery cable the truck will be dead by morning.

We have checked all fuses and have changed battery and alternator

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Dec 12, 2011 at 9:02 PM
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JDL
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Check for voltage to and from the headlamp switch. Got to start somewhere. Did you check for voltage to the applicable fuses? Use a voltage tester.
Dec 12, 2011 at 9:30 PM
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JDL
  • ✓ASE Certified Mechanic
  • 16,098 POSTS
  • ASE Certified Mechanic
My wiring for your model year isn't the best, as far as headlamps. Click on the link.

As far as a battery drain. You pull/replace fuses one at a time till the drain goes away. When you pull the fuse on the problem circuit, the drain goes away.
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Dec 12, 2011 at 9:49 PM
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