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60408CC
09-28-2009, 10:29 AM
has this happened to any one else?

it started about 2 weeks ago by battery light started to come on below like 1500 rpm. thought my battery was going out. over the next two weeks the battery light comes on all the way up to 2500 rpm now...

went to wall mart took the battery that i purchased there about a yr ago. had it exchanged put it in the car and the same thing is happening....

what is going on ... do i need to replace my alternator or what

thanks
Nigil Wonnacott

Oldblueaccord
09-28-2009, 01:19 PM
Your altenator is probably not charging. Get it tested where you got your battery. Keep your battery charged in the meantime if your driving it.



wp

nswst8
09-28-2009, 01:45 PM
Simple shadetree trick. Multimeter the the battery while the car is running see if you are showing 14 volts +/- a half volt. If it is charging under 13 volts check your belt 1st then have a load test put on the Alt.

AccordB20A
09-28-2009, 07:29 PM
sounds like alternator brushes for sure if its going off when you rev the engine up

the battery light has nothing to do with the battery its to do with the charging system.

1987AccordLx-i
09-28-2009, 08:02 PM
Simple shadetree trick. Multimeter the the battery while the car is running see if you are showing 14 volts +/- a half volt. If it is charging under 13 volts check your belt 1st then have a load test put on the Alt.

+1 on the load test

Hauntd ca3
09-28-2009, 09:11 PM
just dont forget that if the battery is fairly flat the alt will be charging at a pretty high amperage so the voltage will be down.
duz sound like brushes to me.
a set of brushes will cost you a few dollars to buy if you can put them in yourself.

JFern
09-29-2009, 08:37 PM
Alternator is definitely bad, this is a common mistake people make at my work. The "Battery Light" coming on does not indicate a bad battery, it is pretty much a "Charging Light" that turns on when your alternator doesn't charge above ~ 13V. You should get a good test on the alternator to see if its the brushes (low voltage) or the diodes that are bad (called excessive ripple)

Hauntd ca3
09-29-2009, 10:52 PM
a simple diode/rectifier test
grab your multimeter if you have one
set it to the 10 amp or more setting
remove a batt clamp and put the ammeter between the batt clamp and the batt.
i,e 1 prob on the clamp and the other on the batt post
a stuffed diode will show up as a 3 or 4 amp reading( this depends on the altenator as some have a low resistance rotor so will drw more current) which is roughly what the rotor will draw.
a leaky diode will show less current than that tho but will still mean your alt needs an overhaul.
most cars will show 20 to 75 milliamps as that is about what gets drawn for clock and radio memories.
just make sure the key is in the off pos and all the doors are shut.
with low brushes, the voltage may seem alright or slightly below normal with just a very light load but the voltage will drop to stuff all when you crank the a/c and all the rest of the acc

b20a86lude
10-04-2009, 03:17 PM
man this ? comes up so frequently. i was mechanic for 6yrs and i keep telling people i dont know y car manfactures put a battry. on the indicator .
but when a battry light comes on its saying hey the alterantor is fucked go check it. they should of put a alternator there but i guess peoepl who dont knwo cars would think it was a rim. my guess they put a battry light was to show people something wrong with ur electrical system.
think about it theres absoulty no sensors on a battry at least on our cars, only sensor that would tell that is all the ones in the alternator,

so to sum it up go change ur alternator, also check the main plug that plugs in to it. it mite be loose,

SOHC
10-04-2009, 09:26 PM
I Had The Same problem, but it was just that My Alternator was Shitting out. Plus the wire was loose also, so just do a General check of your connections.