I notice lately that my voltage is barely above 12V while the engine is running.
03-26-2008, 03:05 PM
#1
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I notice lately that my voltage is barely above 12V while the engine is running.
At first startup it will be near 14V, maybe 13.7V but after the car runs for awhile is will go back down to near 12V. With the car off but accessories on, it will sometimes dip below 12V. Is my alternator on its way out? I figure if the alternator is dying it's probably not charging the battery all the way and causing the low voltage when the engine is off.
Is there a way to figure out if the original alternator is a Bosch or Valeo without pulling the bumper off?
Is there a way to figure out if the original alternator is a Bosch or Valeo without pulling the bumper off?
03-26-2008, 03:16 PM
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That sounds quite normal to me. You should be very close to 12V...
with the car off AT THE BATTERY, but by the time you get to the accessories and the gauge, you should be in the high 11's or so.
Does the voltage drop with the car running when you turn the access. on and off?
If you want to see what brand the alt is, just take the belly pan off and crawl under and see if it's printed on the bottom of the alt. If not, you've gotta take it out.
Does the voltage drop with the car running when you turn the access. on and off?
If you want to see what brand the alt is, just take the belly pan off and crawl under and see if it's printed on the bottom of the alt. If not, you've gotta take it out.
03-26-2008, 04:33 PM
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Actually I get 12V with the car running. Only right after startup I get 13.7V.
Eventually it drops back down to a little over 12V. I notice it especially when driving in heavy traffic.
03-26-2008, 04:56 PM
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Hence the concern in the original post.
I figure either the voltage regulator is crapping out or the alternator itself is ready to go. Either way, gotta replace the alternator.
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03-26-2008, 05:29 PM
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You could try measuring the voltage with a multimeter.
I think it should be ~13.8-14.3v at idle running through the battery and 11-12v with the car off. When monitoring real time data (like temperature or voltage) with a computer I've noticed how vague those gauges are. I've had alternators or voltage regulators go out before in other cars with no warning on the gauge.
