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Alternator voltage problems..

  • Thread starter Thread starter MAXX RS4
  • Start date Start date Feb 22, 2006
M

MAXX RS4

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Jun 1, 2005
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Feb 22, 2006
#1
  • Feb 22, 2006
  • #1
While my car is running the voltage reads 13.6V at the battery. I believe it's supposed to be between 14-15volts, correct? Is this a sign that the alternator is going out or could it possibly be the voltage regulator? Thanks.
 

03ghoststang

Well-Known Member
Jul 16, 2005
1,930
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Los Angeles, California
Feb 22, 2006
#2
  • Feb 22, 2006
  • #2
MAXX RS4 said:
While my car is running the voltage reads 13.6V at the battery. I believe it's supposed to be between 14-15volts, correct? Is this a sign that the alternator is going out or could it possibly be the voltage regulator? Thanks.
Click to expand...


that seems about right it should be between 13.5 to 14.5 so your good
 
M

MAXX RS4

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Jun 1, 2005
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Feb 22, 2006
#3
  • Feb 22, 2006
  • #3
03ghoststang said:
that seems about right it should be between 13.5 to 14.5 so your good
Click to expand...

OK.. Thanks.
 
N

n0v8or

10 Year Member
Aug 23, 2003
604
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Rhode Island
Feb 22, 2006
#4
  • Feb 22, 2006
  • #4
The battery charge voltage intentionally designed to compensate for temperature (you will measure a higher voltage when the alternator is cold). See page 4 of this document for a temp-voltage curve. Remember, this is the internal alternator temperature, not the outside temperature (they will be the same if the engine has been off overnight).

http://www.onsemi.com/pub/Collateral/CS3361-D.PDF
 
M

MAXX RS4

New Member
Jun 1, 2005
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Feb 22, 2006
#5
  • Feb 22, 2006
  • #5
n0v8or said:
The battery charge voltage intentionally designed to compensate for temperature (you will measure a higher voltage when the alternator is cold). See page 4 of this document for a temp-voltage curve. Remember, this is the internal alternator temperature, not the outside temperature (they will be the same if the engine has been off overnight).

http://www.onsemi.com/pub/Collateral/CS3361-D.PDF
Click to expand...

I have a temperature gun, but what exactly should I aim it at?
 
N

n0v8or

10 Year Member
Aug 23, 2003
604
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39
Rhode Island
Feb 22, 2006
#6
  • Feb 22, 2006
  • #6
Well, if you want to be that precise, the end of the alternator where the electrical connector is located. Keep in mind that the accuracy of the curve is probably something like +/-0.5V. So if the curve indicates 13.7V and you measure anything between 13.2V - 14.2V, I wouldn't worry about it.
 
J

jredwood301

New Member
Feb 23, 2006
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Feb 23, 2006
#7
  • Feb 23, 2006
  • #7
VOLTAGE QUES

U MAY BE GETTING LINE DROP AKA VOLTAGE DROP. CHECK CONNECTS TO SEE IF THEY ARE CLEAN. BECAUSE BAD CONNECTS CAUSE GREATER RESISTANCES TTHEREFORE U GET LESS VOLTAGE.
 
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