[Inate]

last night when i was driving home i had the voltage drop to around 10-11 amps, when i finally got home and shut the car off, the battery was acting dead, it still had enough juice to turn the car over, but it wouldn't start it...
now in the morning i went out did nothing but disarm my alarm, and i went in and it turned over fine, not even a slight chug...
now later in the day driving, i parked my car for about 5 minutes, went back in turned it on and now the red light beside the voltage meter, and my e-brake light are on steady now while driving, i can't find anything anywhere about that being an error code or anything, now one thing i know for sure is my e-brake IS disengaged, i stopped completely a few times and played with it, fully engaging it and then disengaging it, the e-brake light still does not go off...
now with the voltage light, it doesn't look like it's running any lower than barely under 12 amps, the car starts fine etc... has done so a few times now over the course of a couple hours, i've disconnected everything stereo-wise, i've been checking my grounds they all look fine, the alarm goes on and comes off no problem, do you guys have any tips for me? im really really really confused...
my car is an 84 P-Type Automatic, this problem has just come out of the blue at me, usually it's my stereo drawing to much current if i see the voltage drop like that, so that's always the first thing i disconnect...
any help would be greatly appreciated

 

[zank]

your Alternator is going south (bad)

 

[Inate]

you seem pretty sure about that...
so im guessing you have some idea of what your talking about, cuz i have NO clue, lol
so what im seeing is basically the car is running off of what juice is left in the battery really right?
man and i just replaced that starter :'( *whine*
lol thanks for the tip too!

 

[CJSREDPRA]

Trust us, we're VERY sure this is what has happened.

Brake light + voltage light + Voltmeter guage is hovering around 11V?? Definitely means that you alternator has died. Want confirmation??? Hook up your digital multimeter to your battery w/ the motor running. The multimeter SHOULD say that you are running around 14V. If it says you are at 11V - 12V, then your alternator is toast.

This has happened to others here before, so we're pretty sure about this.

Get your alternator replaced soon (before the battery dies completely & you're stranded somewhere), or plan on recharging your battery overnight on a daily basis & don't plan to drive very far. And drive w/ all of your accessories turned off as much as possible.

BTW, a dying alternator won't throw a error code in your check engine computer. All it does is turn on the before mentioned warning lights...

 

[Tanya]

I have a ? what if I've replaced my alternator recently and it still charges at 12 volts? and yeah I had to buy the cheapest one b/c I didn't have tons of money to spend at the time, I got my alternator at Advanced Auto Parts./...also recently, and this has happened quite a bit after the new alternator has been out on, it seems to have a "weak start"...
meaning the engine cranks over rather slowly a few times before catching and turning over. Battery is new, alternator is new, is my starter shittin the bed now? lol darnit

 

[CJSREDPRA]

Where are you taking the reading at??? The voltmeter guage itself, or a digital multimeter??? The voltmeter reading will be slightly inaccurate, you need to do it w/ the multimeter hooked up to the battery w/ the motor running & all the accessories turned off.

As for starting.... If the alt was dead & you were driving it for quite awhile, did you try recharging the battery first???

 

[Tanya]

well, I kinda figure that the cars voltmeter is slightly innacurate, but it can't be so much, b/c when I 1st got the car it charged above the 12V mark, usually where I'd imagine 13.5-14 would be. When the alternator died, I replaced the battery and the alternator so neither was older or went through more torment than the other. It was suggested to me that the starter was starting to slowly go bad, but I just wanted to get an opinion on here 1st

 

[Inate]

thanks a lot for all the tips guys, now i can go into the shop and NOT look like an idiot when i ask for them to fix something, lol
you guys are always so handy!
God Bless

 

[SupraWes]

Next time buy a cheap alternator at Autozone, they allow unlimited lifetime warranty returns, Advance Auto will only give you 1.

 

[Tanya]

ugh, nearest AutoZone here is about 45-50 minutes away, it's kinda hard to get there if your alternator is dying, heh

I would have definitly gone somewhere better, but everyone else was asking damn near $200

 

[Dave A.]

The dash guage is a voltmeter and monitors the charging voltage (DC Volts), not charging current ( DC Amperes). With the engine running at a fast idle or higher, the needle should stay dead set right at about 14 volts regardless of how many accessories are switched On (huge stereos excluded :wink: ). If the voltmeter reads lower than 14 volts at any time the engine is above idle speed, monitor the charging voltage directly across the battery with a DMM like Chris mentioned and see if the dash guage is giving you a false reading. If the charging voltage reading across the battery reads low as well, check the fuses in the charging circuit and if no blown fuses are found, suspect a bad alternator or possibly a bad cell in the battery.
HTH!

 

[tdream]

Autozone replacement

Go with autozone. I bought my alternator back in 94 and since replaced it around 4-5 times, again last night. I took the core back and without a question they gave me another one and no cost to me. Keep your reciepts and use the lifetime guarentee they give you.