Alternator or something else?
 

Hi all,
I first noticed something when my car would go to idle on stops or in park that my battery symbol would come on but as soon as i went above idle, it disappeared.

Later on, I was on my way to pick up my brother from work driving along Bridgeport from school. As i was driving, with no warning lights at all and no batter symbol, all my gauges turned off, deck turned off then on. Didn't freak out, tapped the gas and car was still running, just no gauges to tell anything. Then thought alternator, just not enough juice from the battery to power my electronics, well most of them.

Got to my brothers work place, and surly enough when i tried to start the car again, it just made clicking noises as to a dead battery and for sure we thought it was the alternator.

Got it towed by my uncle, get to my house, uncle tells me to start the car, and sure enough it starts, no problem, everything works, and the alternator is charging the battery even as the RPM's dropped to idle. Now i'm confused.

BTW I drive a 2004 Honda Civic Si with an EM2 Chassis, everything bone stock, except for an aftermarket head unit.

Sounds more like a battery going than alternator failing
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Yeah, i think the battery might be going. checked with a multimeter to see if the battery was charging and it was at around 13.8-14.5 volts, which i know where it should be at. Also tested the alternator by removing the negative terminal when the car was running and car was still running, which my friend said the alternator was fine. Going to get the warranty papers from my sister-in-law for the battery and going to replace it. I'll check back with the results.
Thanks for your answer.

could b a bad battery, or alt, or even poor grounds, never rule out poor grounding! do you ever have troubles starting the car in the morning?

sounds more like alternator than battery. If battery is toast too, likely because of age and/or alternator not charging

sounds like a combination of the two i would also check your master relay

If an alternator is dying, you'll hear a high-pitched whine, getting louder as you rev up. If you don't hear this chances are your alternator is fine.

Bad grounds maybe - are both your battery posts clamped tight, and is your battery negative - chassis wire in good condition?

bad alternaters dont always whine. When the engine is revved above idle and turned the light off, that sounds like worn brushes in the alternator. If it was a bearing or diode problem, i could see it whining.

^^whats a master relay?

Had a similar issue with my Corolla, sudden loss of electrics and the charge light intermittently turning on. Turned out to be a bad alternator with very worn slip rings and brushes.

Take the alternator apart and take a look.

Yeah, it was the alternator...
 

Took it to the mechanic, diagnosed it and it was the alternator because as the car would go to idle, the alternator wouldn't charge the battery. we checked everything else, fuses, battery, grounds, etc. Replaced it, and the worn belts, now she runs good without any problems. Took around an hour and a half to do and cost around $150, so all in all it's was a good day. Haven't replied in a while because i had 3 exams this week, so it was just study study study, but thanks everyone and have a good day :)

so finally you go the problem where it was . In my opinion if car is creating the problem so we have to bring directly a good car care shop it will be your saving of time.