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Alternator problem

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Old 04-19-2009, 06:47 PM
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Alternator problem

Alternator is charging battery at 15.56 volts and dash light is on, I suspect a bad voltage regulator what do you guys think and were is it located? is it in the alternator? or is 15.56 normal for MB? if it is normal what else would cause the battery light to come on?
Old 04-20-2009, 07:22 AM
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First make sure you battery fluid level is correct, it can affect the charging system. Most likely though the alternator regulator has failed internally and should be replaced ASAP to prevent possible damage to any control units.

It's located on the back of the alternator, if you haven't done one before then it's best to remove the alternator, it can be done in the installed postion though.
Old 04-20-2009, 08:17 AM
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Originally Posted by Ausmbtech
First make sure you battery fluid level is correct, it can affect the charging system. Most likely though the alternator regulator has failed internally and should be replaced ASAP to prevent possible damage to any control units.

It's located on the back of the alternator, if you haven't done one before then it's best to remove the alternator, it can be done in the installed postion though.
15.56 is TOO high and could eventually damage electrical components.

I agree sounds like the regulator has failed with alternator on full high output. I agree changing the regulator will probably fix the problem. BUT wait too long.
Old 04-22-2009, 10:44 AM
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Originally Posted by Ausmbtech
First make sure you battery fluid level is correct, it can affect the charging system. Most likely though the alternator regulator has failed internally and should be replaced ASAP to prevent possible damage to any control units.

It's located on the back of the alternator, if you haven't done one before then it's best to remove the alternator, it can be done in the installed postion though.
I have to thank you for the advice. I ordered the regulator and since you mentioned it I did it without taking out the alternator. It was way to easy, less that an hour and a half statr to finish. That was the problem and today all is good. No known damage as far as I can tell so far.

vettdvr - like the vette !! I have a silver '02 I love to drive. Hope to get a C6 someday.
Old 04-26-2009, 02:00 AM
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yeah, mine was overcharging the battery without me knowing. it started to smell like really strong rotten eggs. thought it was the catalytic converter, but turns out i was boiling the sulfuric acid in the battery!
Old 05-09-2009, 08:34 AM
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Originally Posted by Rod Spohn
I have to thank you for the advice. I ordered the regulator and since you mentioned it I did it without taking out the alternator. It was way to easy, less that an hour and a half statr to finish. That was the problem and today all is good. No known damage as far as I can tell so far.

vettdvr - like the vette !! I have a silver '02 I love to drive. Hope to get a C6 someday.
There's a new C6 2008 still on the lot here locally.

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