HELP: Battery or Alternator? I am thinking Alternator. Symptoms:
08-29-2007, 07:14 AM
#1
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HELP: Battery or Alternator? I am thinking Alternator. Symptoms:
Working fine until last night.
Started car. Everything fine, but both turn signals flashed fast (like a bulb is burnt out), but hazard flashed normally.
Drove about 8 miles home. No other symptoms.
THEN... "Battery" indicator come on in dash. 30 seconds later the center display dimmed down. HIDs went out, bulb out indicator came on, ABS and airbag and a few other lights came on. I turned the HIDs off, the center display brightened back up. Car running normally the whole time. I got it in to the garage and turned it off. It won't turn over again. Battery voltage is 10.2 volts.
I am thinking alternator, since I lost voltage while running (you should not need a battery while running, at least that is my understanding). Loss of alternator would mean I was running on the battery voltage only - is that possible at night for ~10 miles?
The board's troubleshooting verdict and suggested route of solution?!
Started car. Everything fine, but both turn signals flashed fast (like a bulb is burnt out), but hazard flashed normally.
Drove about 8 miles home. No other symptoms.
THEN... "Battery" indicator come on in dash. 30 seconds later the center display dimmed down. HIDs went out, bulb out indicator came on, ABS and airbag and a few other lights came on. I turned the HIDs off, the center display brightened back up. Car running normally the whole time. I got it in to the garage and turned it off. It won't turn over again. Battery voltage is 10.2 volts.
I am thinking alternator, since I lost voltage while running (you should not need a battery while running, at least that is my understanding). Loss of alternator would mean I was running on the battery voltage only - is that possible at night for ~10 miles?
The board's troubleshooting verdict and suggested route of solution?!
08-29-2007, 07:20 AM
#2
sounds like the alternator...although if your battery is aging...you may need to replace it since
the current one may not be holding a charge from the perfectly good altenator. i would swap battery out first if its old first.
08-29-2007, 07:37 AM
#5
doesn't sound good. check the pos/neg terminals...could be loose. then check belt to
the altenator. you can get the altenator checked to see if its good or not, which is what i would do. could also be a bum new battery...that has happened a few times.
08-29-2007, 07:42 AM
#6
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Well, your battery provides somewhat of a regulator for your alternator......
If you can get it started and measure the voltage at the battery, it should be up to aprox 14v, supplied from the alternator. Your alternator puts out slightly more than your battery, the higher potential is what charges the battery.
08-29-2007, 07:43 AM
#7
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I was hoping for a bum battery, but it should run fine on the alternator then, right? Belt seems
fine.
Guess I need to hit up SparTTan's alternator write up, but I don't have much free time right now...
Guess I need to hit up SparTTan's alternator write up, but I don't have much free time right now...
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08-29-2007, 08:12 AM
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Almost exact same symptoms for me 2 months ago... (updated)
when it was at it's worse, dash lights started dimming and fading and battery light came on when stopped at traffic lights. Revving up the engine for a few seconds seemed to charge it up again... then back it came back. When it first happened, doing some interstate driving seemed to make it hold up for a day, but later on it didn't help.
Changed the battery and everything has been perfect ever since... I'd say try the battery first.
FWIW... I think, what drained it was the stupid problem of the radio coming back on after taking out the key and opening the door -- when my radio is turned all-the-way down, I cannot tell if it comes back on. I've gotten used to just turning it off everytime I park.
Changed the battery and everything has been perfect ever since... I'd say try the battery first.
FWIW... I think, what drained it was the stupid problem of the radio coming back on after taking out the key and opening the door -- when my radio is turned all-the-way down, I cannot tell if it comes back on. I've gotten used to just turning it off everytime I park.
