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Battery going dead

  • Thread starter Thread starter rirvan79
  • Start date Start date Jan 9, 2006
R

rirvan79

New Member
Jan 9, 2006
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Jan 9, 2006
#1
  • Jan 9, 2006
  • #1
I have a '01 GT and the battery keeps going dead. the battery and alternator tested good. i hooked up a test light from the ground cable to the ground post on the battery. the light was on. i started pulling fuses and the light went out when i removed a 40 A fuse in the power distribution box. the owners manual labeled the fuse instrument cluster, pcm. if anybody knows what might be wrong, please let me know
thanks
 

COramprat

...I can take it. I think.
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Jan 9, 2006
#2
  • Jan 9, 2006
  • #2
Sounds like the PCM is drawing power for some reason. I'm not certain...maybe some more help will pop in.
 
R

rirvan79

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Jan 9, 2006
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Jan 10, 2006
#3
  • Jan 10, 2006
  • #3
someone told me that it may be a battery saver relay, i have never heard of it and cannot locate it anywhere
 

chris kelvin

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Sep 11, 2005
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Jan 10, 2006
#4
  • Jan 10, 2006
  • #4
coramprat sounds about right there.

Are you sure the alt tested good..? How is the battery exactly going dea, you mean like overnite when the car is off..it wont start in the morning..?

If that's the case the battery is not getting charged, OR more likely the battery is FHUGGED. Once a battery goes dead, it's DEAD...PERIOD. You can recharge it, but it is all FHUGGED up inside. A deep cycle battery can be re-lifed.

If it's the stock battery, buy a new one. Battery's are only good for 3, 4 years TOPS...trust me on that. If you can't find the problem get a trusted...TRUSTED mechanic to look her over, not one that's gonna say you need a new alt/batt etc.

BTW not to sound negative, but 01 was a long time ago, alts and batts suck in general and should be changed if you have the spare $$$ laying around, it's easy enough..

PS i never heard anything called a battery saver relay...? It's either something draining the battery, or the battery is gone and wont hold a charge...i seen this ALL the time at autozone, guy thought the battery was good after 5 years...wanted us to charge them, we did, then they got home, put in the battery and it died the next day.
 

1LowGT

New Member
Sep 4, 2005
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st louis mo.
Jan 11, 2006
#5
  • Jan 11, 2006
  • #5
buy an optima if your battery turns out to be the problem
 
R

rirvan79

New Member
Jan 9, 2006
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Jan 11, 2006
#6
  • Jan 11, 2006
  • #6
battery is brand new, got it 3 weeks ago because i thought that was the problem, only loses charge if it sets a couple of days
 

newstangman

New Member
Mar 31, 2005
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Long Island, NY
Jan 11, 2006
#7
  • Jan 11, 2006
  • #7
chris kelvin said:
PS i never heard anything called a battery saver relay...?
Click to expand...

Battery Saver Relay shuts off all accessories after 15 - 30 seconds of locking car. Try turning radio on and leaving it on high volume. Exit and lock car and see if it gos off or stays on. If it stays on, your Battery Saver Relay is shot.
 

STNG_96

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Sep 15, 2004
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Marion, Illinois
Jan 11, 2006
#8
  • Jan 11, 2006
  • #8
Ive had to replace my alternator in the past because it had a short in it, and would kill the battery overnight. It still made power and all when on, but it would continue to drain the car throughout the night, and would kill it. I just unplugged it one night and the battery was fine the next day, so I knew that was it.
 

tomustang

Psychotic Member
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Jun 8, 2000
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Feb 27, 2006
#9
  • Feb 27, 2006
  • #9
newstangman said:
Battery Saver Relay shuts off all accessories after 15 - 30 seconds of locking car. Try turning radio on and leaving it on high volume. Exit and lock car and see if it gos off or stays on. If it stays on, your Battery Saver Relay is shot.
Click to expand...
what year did they start putting them in the mustangs?
 

Mike97gt

it doe snot
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Jan 26, 1999
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Feb 27, 2006
#10
  • Feb 27, 2006
  • #10
ok to properly test for a draw you need a multimeter and you can't let the negative post and terminal get disconnected until you have the meter connecting them both. at no point can the terminal and post be completely disconnected.

when the terminal is taken off from the post and you go and connect your test light in there you are reactivating all the modules for about 20 minutes.

only other way is wait about a hour or so after you connect your multimeter ( no test light) then start your diag.
 
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