gearhead06

battery keeps going dead, battery tested to be in perfect condition but alternator failed its third test so I installed a new alternator and it didn't solve the problem the car still goes randomly dead, I had the system tested again and everything test out to be in great working order, I have checked everything for a drain, the only thing I have aftemarket on the car is rims and a air intake on the car with a tune from brenspeed, today I shut the car down before work and listened to just the radio for 5mins or so and it was to dead by the end of the day to start, I'm drawing a blank and cant figure this one out.. I need help...also battery was fully charged after alternator install...

thanks
jason

white08gt

check for a loose ground from engine to frame. friend had same problem on a bronco back in the day 1996.

Nuke

Unless you have some wierd coincidence with bad alternators, I'm stumped. Although this seemed more prone to the '05 thru 07's, are you leaving the head unit on when you shut off the ignition? The amps in the older shakers would continue to draw power if not shut off.

gearhead06

I haven't really messed with the head unit to much, I set everything the way I like it and leave it alone, i do have the upgraded shaker 1000 system, but I never had a problem with the car dying before...

Simon1

I would check all of the connections to and from the battery to the alternator. Then fully charge the battery and have it load tested again. if the car still does it I would have the alternator tested again.

What alt did you have and what did you get?

Are you throwing any codes?

gearhead06

no codes, I have already tested all that I had a stock alternator with 46,000 on it and replaced with a optima alternator just a week ago, I have had the battery fully charged and tested again and had the new alternator tested after installed a few days ago, everything tested out fine, I have shut the car down locked it and sat inside listening and checking everything, checked for trunk lights on and stuff like that to, it just doesn't make a sense... would my amp for the shaker system really just start staying on and if so how do I shut it down manually?

moosestang

How old is the battery?

gearhead06

original battery, car is a 2008 with 46,000miles on it, so battery is 2 years old but test out perfect...

shiftworker

I had a new battery do this to me. but use an ohm meter and disconnect battery on 1 post to check for actual drainage. shouldn't be more than 3 milliamps for you stereo.

moosestang

I would have replaced the battery before doing anything. I only got 3 years out of my stock battery and less than 30,000 miles.

What did you mean by alternator failed third test? if the car stays running, then the alternator is working.