2007 Impala Alternator repair help needed

Old 05-06-17, 07:13 AM
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2007 Impala Alternator repair help needed

I have a good friend who has a dead alternator and no money. If it is feasible. I would like to replace the diodes. Would that have a good likelihood of fixing it? How much work is it. Can a semi skilled like me fix it?
Thanks, Jim
Old 05-06-17, 07:21 AM
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here is video that should help
Old 05-06-17, 12:59 PM
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How do you know the alternator is dead?
Old 05-07-17, 06:46 AM
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Learn to use a multimeter and test things before replacing them. This will save you a lot of time and money.
Old 05-10-17, 02:11 PM
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The diode is in the assembly called a rectifier. These rarely fail on their own, more often they fail because the increasing resistance in the windings, so just replacing the diodes/rectifier might be a short live solution. But they do fail. You can do a simple multi meter test to see if the diodes have failed, lots of you tube videos on this.

Your Impala has a Bosch or Denso unit depending upon which engine it has, and parts are plentiful.

This place has a nice kit and they would probably consult with you up front as they don't want an unsuccessful rebuild.


If you want just the diodes I suspect they would supply as well, but most people just swap out for a new rectifier.

But I get you want to do this on the cheap, so sure it can be done with a bit of research if this sort of thing is interesting to you. I love to fix things, rather than just swap parts, just for the challenge!
Old 05-10-17, 05:30 PM
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I've worked on a lot of GM alternators and the biggest problem I've came across was the internal voltage regulator was defective.

If one or several diodes shorted..... you'd be getting low DC or excessive AC from the alternator.

With very high mileage you could have defective/worn brushes.

Without some basic testing... you're guessing at the problem.

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