» » »

Buick Q&A

Ask Your Question

1999 Buick LeSabre Question: Why does the volt light on the dash come on?



Buick Grand National, Locust Grove, VA, March 29, 2013, 16:25

I replaced both the battery and the 140 amp alternator in this Buick v6.....now the volt light comes on 10 seconds after engine start...the engine runs fine, car runs like new, no starting nor charging problem...took alternaor to AutoZone for check and it passed all checks....putting out 14.67 volts at battery and at the back of alternator....belt is tight, does not slip. Both batter and alternator are new...even checked the connector that goes to the back of the alternator...it's fine, no breaks in wire. How can I get that annoying volt light on the dash to turn off.....the charging gauge on the dash shows charging at 14.67 volts....any help would be great....is this car save to drive now with the volt light on or should I just put a piece of black tape over it?

2 Answers
Flag This
  • Answer #1

    March 30, 2013, 03:17

    try disconnect battery. before hooking up again, coat both post with petrollium jelly. wait a few minutes before reconnecting.

    Flag This
  • Reply

    Buick Grand National, March 31, 2013, 01:34

    Hey, thank you for your answer.....I already did what you suggested, three times....I know this method is supposed to reset the ecm....but this did not work.......I really made sure the first time that the battery connections were cleaned with a brass brush and jelly on them.....the alternator I had from the same company on it before this one, did not trip the light, but it wasn't charging fully, so I sent it back and got this one from them........I'm thinking it might be the alternator, but just don't know....hopefully I could send this one back, but I hate loosing all the shipping costs every time....any other ideas can you suggest for me, please? I'm at my wit's end.

    Flag This
  • Answer #2

    Potomac Creek Automotive (12 Answers) , Fredericksburg, VA - (540) 854-1010
    potomaccreek April 01, 2013, 08:01

    14.6 is high voltage for charging. I would check alternator unit for worn brushes or bad diodes. The light works both was for overcharging and under charging. I would say in this case it is sensing overcharging.

    Flag This