Well, my battery light would come on intermittently, usually for short periods of time and when the car was idle. Then on two occassions (the second being when the alternator failed) I lost power to the headlights, stereo, etc. When I tried to jump it, it would start, but it wouldn't recharge to full power (no headlights, etc.)
thats sounds like just a bad battery, which they were only good for 3 yrs. ive got the oem alt in my 05, 64,000 so far no problems. i think most often its just the battery or battery connections.
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goina hundred in a 55, and i dont know why..
some things were just meant to be..
05 V6 auto, torch red, basic, a few mods
06 V6 stick, vista, premium (g/f`s car)
Well, my battery light would come on intermittently, usually for short periods of time and when the car was idle. Then on two occassions (the second being when the alternator failed) I lost power to the headlights, stereo, etc. When I tried to jump it, it would start, but it wouldn't recharge to full power (no headlights, etc.)
I had the same problem and ended up replacing my alternator a couple of months ago. I stuck a multimeter on the old alt and it was only charging at 12v. Put in a new one and it charges at just a tad over 14v which is what it's supposed to do.
The charging was just low enough that it was slowly depleting the battery without setting off any alarms or tripping any codes until it was too late.
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2005 V6Mustang coupe. Automatic. Black with Charcoal Interior
Mods: JLT CAI, Bamachips 91 race tune, single Mustang V8 muffler, Mustang V8 swaybars
Looks: smoke front turn signals, sequential taillights, 14" shorty antenna, MRT rear window louvers and a little chrome for the interior 2000 C5 Corvette convertible, Torch Red with Black Interior. Full of options, Corsa exhaust 1990 Ford Bronco 351ci engine- it runs.
I had the same problem and ended up replacing my alternator a couple of months ago. I stuck a multimeter on the old alt and it was only charging at 12v. Put in a new one and it charges at just a tad over 14v which is what it's supposed to do.
The charging was just low enough that it was slowly depleting the battery without setting off any alarms or tripping any codes until it was too late.
How many miles did you have on your mustang when you replaced the alt?
i had 40k mile on my car when the alt quit. i was driving home, and all the lights went out, the guages stopped working and my abs and engine lights came on. there was no warning or nothing. took it off and had the local Checker auto test it and it FAILED every test.
How many miles did you have on your mustang when you replaced the alt?
About 65k. I've been trying to nurse the Mustang and not put high miles on it so I've been rotating my vehicles for work. I drive around 70,000-90,000 a year in my job and I don't want to pile it all on one vehicle.
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2005 V6Mustang coupe. Automatic. Black with Charcoal Interior
Mods: JLT CAI, Bamachips 91 race tune, single Mustang V8 muffler, Mustang V8 swaybars
Looks: smoke front turn signals, sequential taillights, 14" shorty antenna, MRT rear window louvers and a little chrome for the interior 2000 C5 Corvette convertible, Torch Red with Black Interior. Full of options, Corsa exhaust 1990 Ford Bronco 351ci engine- it runs.
i googled alternator problems on mustangs and it led me here i have a 2006 mustang with alot of miles on it and tonight encountered all of the problems that have been listed in this thread. i was going to the gas station and a couple blocks away all my electrical went out and i made it to the station went to start it again and nothing and the AAA guy came out started right up then i went to turn on my headlights and nothing then everything shut down the tow truck guy said it was the alternator. WAS BASICALLY WONDERING HOW LONG IT TAKES TO FIX AND HOW MUCH IT SHOULD COST!!!!!!!!!!!! I HAVE A REPUTABLE MECHANIC IVE USED FOR YEARS BUT JUST WANT A HEADS UP !!!! THANKS !!!!!!!!!!
Why You Yelling?......its an easy enough job you could do an altinator yourself in your driveway...so basically just the cost of the altinator and your time.
2006 V6 Mustang alternator problems 
......its an easy enough job you could do an altinator yourself in your driveway...so basically just the cost of the altinator and your time.
