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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Dead battery light is turning on and off HELP!! PLEASE!!

  • Thread starter Thread starter imGOINGin!
  • Start date Start date Sep 17, 2009
I

imGOINGin!

New Member
Sep 17, 2009
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Sep 17, 2009
#1
  • Sep 17, 2009
  • #1
I have a 2003 Svt Cobra. My red dead battery light keeps turning on and off! My batter has been tested and it is in good shape. ANY ONE KNOW WHAT COULD BE THE PROBLEM???
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
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Sep 17, 2009
#2
  • Sep 17, 2009
  • #2
Take the car to AutoZone to have the entire charging system tested for free in the parking lot. Also check battery terminals for solid connections.
 
I

imGOINGin!

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Sep 17, 2009
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#3
  • Sep 17, 2009
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thank you I will do that
 

Stark77

Member
Jun 11, 2008
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Tallahassee, FL
Sep 17, 2009
#4
  • Sep 17, 2009
  • #4
Are you running underdrive pulleys? If so, this could be one cause if your light is coming on at low speed/RPM. My battery light comes on all the time, but my voltage doesn't drop. Once you get it scanned, if it doesn't throw any codes, I wouldn't worry about it.
 
I

imGOINGin!

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#5
  • Sep 17, 2009
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No no underdrives. Yeah but its just annoying to see it turning on and off..
 

twogts4us

15 Year Member
Apr 1, 2004
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79
Dunedin, FL
Sep 17, 2009
#6
  • Sep 17, 2009
  • #6
Likely the alternator. My 02 GT ate them like breakfast. Fortunately that was when it was still under warranty..I must had hit a bad batch of them...I went thru about 6 of em in 2 years!
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
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134
Sep 17, 2009
#7
  • Sep 17, 2009
  • #7
I agree it is probably the alternator. On Cobras they fail MUCH more often because they are in a different and far hotter place. There is a guy on Modular Fords that has an awesome alternator thread going and re-manufactures Cobra alternators. Check it out...
 

joshjwc9

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Jun 12, 2006
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Palm Harbor, FL
Sep 17, 2009
#8
  • Sep 17, 2009
  • #8
I have had a friend with a 03 Cobra go through the same process. I believe after going through several, he went out and got a higher amp PA one. He bought it through a reputable seller online and hasn't had to send it in for warranty since he did that. He holds onto his stock one in case this PA one craps out on him..
 
I

imGOINGin!

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#9
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  • #9
I wish it was the Alternator but I got it tested and thy said it was fine. I will get it re tested just to make sure but My guess is a bed sensor
 

GDawg

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Sep 18, 2009
#10
  • Sep 18, 2009
  • #10
imGOINGin! said:
I wish it was the Alternator but I got it tested and thy said it was fine. I will get it re tested just to make sure but My guess is a bed sensor
Click to expand...

There is one wire from your alternator that feeds that warning light. Check fuse #5 (15A). Pull it out and really check it. That may be the cause.


 
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