If a voltmeter reads 13.3 volts with the car running, is the alternator weak? Wife's car... '09 IS250.
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If a voltmeter reads 13.3 volts with the car running, is the alternator weak? Wife's car... '09 IS250.
From a quick google search found this at: http://www.w8ji.com/battery_and_charging_system.htm to charge the battery, the alternator voltage output has to exceed a minimum charging voltage. This minimum charging voltage is 13.8 volts dc across the battery terminals, or at the output of the alternator. A single lead-acid cell starts to charge at anything over 2.25 volts. Since a 12 volt battery has six cells, any 12 volt lead-acid battery needs at least 13.8 volts to start to charge. This voltage will be enough to fully charge or maintain the battery on a trickle charge, but charging time will be very long at 13.8 volts.To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts. Above 14.5 volts charging voltage, batteries have a greatly increased tendency to release excessive acidic vapors, hydrogen gas, and to corrode things around the battery. The battery terminal charging voltage must be less than 14.7 volts to prevent excessive gassing. Charging voltages over 14.7 volts can prematurely dry the battery by boiling out electrolyte, and increase risk of a battery hydrogen gas explosion.
^Thanks Keith...did a bunch of googlin' myself, but found several different answers. I think 13.3 is low FWIW.
I stopped after I found the link I posted... guy had lots of pictures, words and numbers so he must know what he's talking about :-). anyway, yeah, sounds weak to me too. Autozone should be able to hook up their charging system tester and check it out easy enough if you want another data point.
All started when she took it to Lexus for 50K mile checkup....they said weak battery. Wife then took it to AZ since battery was still under warranty...they said weak alternator.
I was going to say weak battery as well. Yank it out and get it tested!
Is she getting a battery light or a CEL? You'd think the lexus would know if the alternator was out of spec and tell ya.
That answer saves them them from having to do anything. AutoZone Counter Jockey not normally someone I hold upon high for their vast knowledge of automotive type stuff. ;-)Quote:
Originally Posted by sammm
^She's going back to Lexus this afternoon and have them check out the alternator...you would think that's part of the 50K checkup, but it's not.
Lexus says alternator checks out. Have the battery on the trickle-charger now...
Go get it a new battery.
Because when it strands her she will be able to say, "I told you there was a problem". And I can tell you from experience that ain't good! ::Bop::
Sounds painful... As punishment will Sammmm be forced to attend Quilting shows?Quote:
Originally Posted by POS Racing
That would be getting off easy! ;-)Quote:
Originally Posted by Keifersmith
Anything but that!Quote:
Originally Posted by Keifersmith
If the amp gauge isn't at zero in the morning, back to AZ it goes.Quote:
Originally Posted by POS Racing
How old is the Battery?
3 years in November.
Wife complained the car was cranking slow again. Put it on trickle charger last night, and charger read 9 amps. Checked a few hours later and it was down to 2-3 amps.
Went out this morning to disco. the charger and it was back at 9 amps.
That sounds like dying battery to me.....thoughts?
You still haven't replaced that battery??
I need to convince my friends at Vatozone.
At 3+ years is their any warranty even remaining on that battery??
How much is an ECU for a Lexus when it gets fubared due to low voltage / high current or an improper jump start??