1999 GMC Sierra Question

1999 GMC SIERRA
140,000 MILES • V8 • 4WD • AUTOMATIC
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TODD4123
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  • 2 POSTS
We put the truck in reverse and all the warning lights on the dash came on. The truck stayed running however the idle would slow down and the lights would go dim. The volt meter would drop down to 9amps and then go back up. The time on the radio reset it self. At one point the engine stoped. It does not happen all the time. Does this sound like the alternator?
Jan 23, 2010 at 9:29 AM
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MMPRINCE4000
  • ✓ASE Certified Mechanic
  • 8,548 POSTS
  • ASE Certified Mechanic
Alternator is a possibility.

Take truck to any autoparts store and have charging system tested, battery, alternator, starter draw.

This will tell you if alt. is problem.

If this happens only when in gear, then you may have a bad motor mount causing excessive engine movement and possibly pulling on a wire harness to the point that it is causing the circuit to be opened.
Jan 23, 2010 at 10:13 AM
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