what do i check for?

1994 GMC SIERRA
205,000 MILES
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NATIONSDOUG
  • MEMBER
  • 1 POST
Was driving down the road and everything jus shut off at once and now nothing comes on
May 4, 2012 at 4:40 AM
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CARADIODOC
  • ✓ASE Certified Mechanic
  • 34,321 POSTS
  • ASE Certified Mechanic
Measure the battery voltage first. If it's 12.6 volts, it's fully charged. Check the smaller red positive battery cable where it attaches to the under-hood fuse box. Be sure that connection is clean and tight.

If the battery voltage is around 12.0 volts, it is discharged. Suspect the generator. Charge the battery, then measure the battery voltage again with the engine running. It must be between 13.75 and 14.75 volts.
May 4, 2012 at 5:12 AM
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