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What was the voltage of the battery after charging the battery out of the car before putting it back in the car?
Why pull the alternator????? If it won't start without a jump immediately after charging the battery out of the car, the alternator is nowhere in that picture. It doesn't need the alternator to start and cranking doesn't turn the alternator enough to put out any voltage. Most likely the battery is bad given the inability to start the car on its own and the quick voltage drop. Each of the 6 cells inside the battery put out around 2.2 volts each. If the battery has a weak cell, it may show decent voltage under no load after a fresh charge, but then drop to close to zero when any heavy load is put on it. If something was wrong with the starter itself draining too much current, you'd probably have a difficult time jumping it as well.
It's good that there is no drain after removing the defroster fuse. It's typically unlikely for 2 components (defroster relay and battery) to go bad at the same time, but if the defroster relay was stuck on, then multiple drain cycles could have killed the battery.
I'm very confused why you don't take it to a shop for evaluation. Any competent battery shop will have the right equipment and be able to pinpoint the problem (battery, voltage regulator, cables, ground strap, alternator ...) in a few minutes. Usually the charge for that test is minimal or free. Pulling the alternator on a hunch seems like a massive presumption, especially since it doesn't explain why your battery won't start the car after a full recharge.
I work long days and generally only have time to play with it at night. Plus chasing things down is half the fun!
The battery was reading 12.3 after the charge. I had it tested when this all started and it was fine. maybe i should get a second opinion?
As for the Alternator, there was an incident recently where all of my warning lights across the bottom of the dash went crazy and flashed on and off for about a minute while i was driving. that seemed very "alternator-y". If its not the culprit Ill throw it back in. I did uncover some bad pulleys in this process so I'll replace those as well while im in there.
Mainly, I have 2 small kids (2 and 5 months) and a wife, so any time I can spend in the garage with the music on and a wrench in my hands is relaxing for me. "Can you bathe the kids tonight? I've got to figure out this car situation..." Most of my time in the garage is actually spent quietly staring at the wall.
12.3 volts after a full charge is not good, so if it was charged long enough with something stronger than a trickle charger, almost certainly the battery is bad. Trickle chargers are for maintaining voltage, they take forever and a day to recharge highly discharged batteries.
If you used a trickle charger, that could explain the low voltage without the battery necessarily being bad (which would explain why it didn't start on it's own and could lend credence to an alternator or voltage regulator problem because the voltage dropped in use). If you used a real charger, the battery almost certainly is bad.
Originally Posted by NickHolloman
I had it tested when this all started and it was fine. maybe i should get a second opinion?
The battery may have been fine then, but it is very possible that the battery was subsequently damaged as a result of the current drain issue. If the root problem does turn out to be a stuck rear defroster relay, that explains your initial issues, and it would have caused your battery to be severely discharged several times (the defroster is essentially a "controlled" short circuit, it's a lot more severe than something like a dome light being left on). Typical lead acid car batteries can't handle multiple deep discharges without being damaged. "Deep cycle" batteries (like those used in golf carts) are designed to handle discharges without damage, but they make lousy car batteries, so virtually all batteries designed for automative applications can't handle severe discharges very well at all.
That's what I was thinking but it was close enough so I wasn't sure.
so if it was charged long enough with something stronger than a trickle charger, almost certainly the battery is bad. Trickle chargers are for maintaining voltage, they take forever and a day to recharge highly discharged batteries.
My charger supposedly acts as a charger and then switches over to a maintainer once fully charged. It's from Harbor Freight so I take that with a grain of salt
Alternator might be fine, as low 13s is just probably regulating the voltage - the battery might not be able to take much charge. The alternator is increasing a 10.5v to over 13, so that means it’s working.
Any battery that’s been fully charged but still reads 10.5V is a bad battery. Especially if you charged it overnight with a trickle charger (0.75-2amps).
The battery showed 12.3 after initial charge and 10.5 after driving and turning the car off. It maintained that 10.5 over night
The battery showed 12.3 after initial charge and 10.5 after driving and turning the car off. It maintained that 10.5 over night
A fully charged battery after stabilizing will read exactly 12.6v. There are 6 cells at 2.1v each, a voltage of 10.5 after stabilizing is exactly what you will see if a cell is shorted, 12.6v - 2.1v = 10.5v
Hi guys, would definitely agree and lean towards that battery not doing so hot on this one. One thing some of you might be interested in to help monitor voltage and performance in a scenario like this would be one of our Bluetooth Battery Trackers. Essentially it will let you monitor your real time voltage without having to go to the battery and the tracker will keep a log showing you that voltage for up to 30 days by using an app on your cell phone. In addition you can set it to send you alerts for low voltage to let you know there might be problem. Lastly you can also perform charging and cranking tests to let you know how the system and battery is doing. Please feel free to check them out as there is an option for Lithium Batteries as well as for Lead Acid Batteries and feel free to let us know if you have any questions.
- chad@antigravitybatteries.com
Last edited by Antigravity; 05-23-2019 at 02:48 PM.
I work long days and generally only have time to play with it at night. Plus chasing things down is half the fun!
The battery was reading 12.3 after the charge. I had it tested when this all started and it was fine. maybe i should get a second opinion?
As for the Alternator, there was an incident recently where all of my warning lights across the bottom of the dash went crazy and flashed on and off for about a minute while i was driving. that seemed very "alternator-y". If its not the culprit Ill throw it back in. I did uncover some bad pulleys in this process so I'll replace those as well while im in there.
Mainly, I have 2 small kids (2 and 5 months) and a wife, so any time I can spend in the garage with the music on and a wrench in my hands is relaxing for me. "Can you bathe the kids tonight? I've got to figure out this car situation..." Most of my time in the garage is actually spent quietly staring at the wall.
I'd rather be driving or at least spending quality time with my wife and kids...
A fully charged battery after stabilizing will read exactly 12.6v. There are 6 cells at 2.1v each, a voltage of 10.5 after stabilizing is exactly what you will see if a cell is shorted, 12.6v - 2.1v = 10.5v
Nick
I Like the LOBSTER CLAW wheels...had them on a 997 that I had a few years ago...
Thanks. I originally set out to buy some OZ wheels but came across these lobster forks and decided to use them for a while. I always liked them. Ill probably swap them out in a few months
05-22-2019, 11:19 AM
