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Battery light is comming on when idling????

  • Thread starter Thread starter WHITE94COBRA
  • Start date Start date Jan 6, 2006

WHITE94COBRA

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Jan 6, 2006
#1
  • Jan 6, 2006
  • #1
When I come to a stand still my battery light comes on and flickers, it just started doing this, I have a 3 month old optima red top, a year old alt, car runs fine when it happens, starts fine, I left my lights on for a while to check battery, car started fine, disconnected the battery when the car was started, fine.... anyone have this problem before, Also the alt has the stock pulley right now I havnt changed it yet...

Any help???
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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#2
  • Jan 6, 2006
  • #2
What is your idle at when the battery light comes on?
Good luck.
 

WHITE94COBRA

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#3
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  • #3
It's at about 650 - 750
 

95BlackTan50

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#4
  • Jan 6, 2006
  • #4
WHITE94COBRA said:
When I come to a stand still my battery light comes on
Click to expand...

What exactly do you mean by "when I come to a stand still" ?

I had the weirdest problem one time. When I came to a hard stop, my battery light would come on, my voltage gauge would drop and my power steering would lose power for a short time, then it would all come back. To make a long story short, I had a leaky thermostat housing and coolant was pooling on top of the water pump. When I came to a stop, the coolant would drain onto the pullys, causing the belt to slip and temporarily disabling the alternator and power steering. Once the friction dried the belt, the pullys would catch and everything started to work as usual.

It's a long shot, but the symptoms seem similar. Good luck
 

HISSIN50

"How long does it take to get help in here?
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#5
  • Jan 6, 2006
  • #5
When this happens, if you goose the RPM's up to around 800, does it improve? I am fighting a similar type of deal right now.
Good luck.
 

bill302

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Nov 2, 2005
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alabama,gadsden
Jan 6, 2006
#6
  • Jan 6, 2006
  • #6
the battery light is the charging system warning indicator. i had the same problem on a windstar van i went to oreillys they tested my charging system the results indicated the voltage regulator was weak i replaced it problem solved.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jan 6, 2006
#7
  • Jan 6, 2006
  • #7
The battery light is in series with the switch and sense wire. If that wire is resistive, it can lead to issues.

An idle that is too low with a high load can drop the RPM's down low enough to trigger the battery light as well. So something like a bad IAC can cause charging system issues.
 

WHITE94COBRA

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#8
  • Jan 7, 2006
  • #8
If I goose the throttle at all it clears up right away... I did notice a little leak on my therm.....hmmmmm
 

95strokerPSU

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Jul 29, 2004
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Sacramento from Philly
Jan 7, 2006
#9
  • Jan 7, 2006
  • #9
bill302 said:
the battery light is the charging system warning indicator. i had the same problem on a windstar van i went to oreillys they tested my charging system the results indicated the voltage regulator was weak i replaced it problem solved.
Click to expand...

Anybody want to give a quick how to on replacing the voltage regulator. My battery light has been on for the past couple months and I believe thats the problem.
 

bill302

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Nov 2, 2005
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alabama,gadsden
Jan 7, 2006
#10
  • Jan 7, 2006
  • #10
 

bill302

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alabama,gadsden
Jan 7, 2006
#11
  • Jan 7, 2006
  • #11
95strokerPSU said:
Anybody want to give a quick how to on replacing the voltage regulator. My battery light has been on for the past couple months and I believe thats the problem.
Click to expand...



HAVE IT TESTED AT A AUTOPARTS STORE BEFORE REPLACING. BUT HERES HOW YOU DO IT.
1. DISCONNECT NEGATIVE BATTERY CABLE

2 REMOVE 4 TORX HEAD SCREWS HOLDING VOLTAGE REGULATOR TO ALTERNATOR REAR HOUSING AND REMOVE REGULATOR WITH BRUSH AND TERMINAL HOLDER ATTACHED.

3. PRY OFF THE CAP COVERING THE A TERMINAL (A WILL BE STAMPED IN PLASTIC ABOVE TERMINAL) SCREWHEAD WITH A SMALL SCREWDRIVER OR EQUIVALANT TOOL.

4. REMOVE THE 2 TORX HEAD SCREWS RETAINING THE REGULATOR TO THE BRUSH HOLDER.

TO INSTALL:

5. INSTALL THE BRUSH HOLDER ON THE REGULATOR WITH THE 2 RETAINING SCREWS

6.INSTALL THE CAP ON THE HEAD OF THE A TERMINAL SCREW

7.DEPRESS THE BRUSHES INTO THE HOLDER AND HOLD THE BRUSHES IN POSITION BY INSERTING A STANDARD SIZE PAPERCLIP OR EQUIVALENT TOOL ,IN BOTH LOCATION HOLES IN THE REGULATOR AND THROUGH THE HOLES IN THE BRUSHES.

8.INSTALL THE REGULATOR/BRUSH HOLDER ASSEMBLY AND REMOVE THE PAPERCLIP . INSTALL ATTACHING SCREWS

9.CONNECT NEGATIVE BATTERY CABLE.

ALSO WHEN YOU BUY REGULATOR MAKE SURE IT COMES
WITH NEW BRUSHES, I BELIEVE I HAD TO PURCHASE BRUSHES SEPARATE. INSTALL IS NOT DIFFICULT AT ALL ESPECIALLY IF YOU HAVE ANY EXPERIENCE INSTALLING BRUSHES.
 

95strokerPSU

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Sacramento from Philly
Jan 7, 2006
#12
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  • #12
Awesome thanks.
 

canadian94gt

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Debert, Nova Scotia,Canada
Jan 10, 2006
#13
  • Jan 10, 2006
  • #13
Could be caused by underdrive pullys also. If you do a lot of city driving you should leave the stock alt. pully on.
 

WHITE94COBRA

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#14
  • Jan 10, 2006
  • #14
My underdrives have been on there for about 2 years, Zero problems, so that has been completely ruled out; now the coolant leak is possible But its such a small amount that it burns off before touching anything. however when the car cool down who's to say it's not leaking then...... I'll keep looking, and i'll fix the leak today.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jan 10, 2006
#15
  • Jan 10, 2006
  • #15
Have you chased alt regulator wires and the primary electrical system connections?

The reg plug wires can start to vulcanize or even break, and resistivity goes up when the wires get hot. THis can create issues.

Also though we know we all do it first thing, go over the battery connections, as well as the motor grounds and alternator cable wiring to make sure they are all clean and tight. STuff tends to vibrate loose over a long time and a loose primary electrical connection can cause such an issue.

Good luck.
 

WHITE94COBRA

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Jan 11, 2006
#16
  • Jan 11, 2006
  • #16
already checked all connections... let ya know more tomarrow
 
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