Alternator problem need help
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Driver School Candidate
Joined: Jul 2018
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From: PA
Alternator problem need help
Hi everyone, so I have been trying to fix this problem for almost a month now. When I tried to start the car, I used the multimeter to check for voltge, the battery gave me 12.2V while engine off, with engine on 11.4V. I knew then that the alternator is bad. I got new alternator still not charging. Then I replaced the 120a ALT fuse and everything started working and the alternator is charging the battery with 14.5V , I let the car for a while just to charge up the battery, turned off and went to sleep feeling happy that I fixed the problem. The next day I went to start the car and battery light turned on. Cheked the battery volts around 11.5-11.7v. What should I do next I’m confused.
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Driver School Candidate
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From: PA
and No I didn’t use a jump cable.
CL Community Team
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From: Japan
My speculation is that the person used a jump cable but the polarity was reversed. This often causes a few to several other problems in addition to the open 120A ALT fuse.
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Driver School Candidate
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From: PA
So the previous owner had blown the fuse. I worry that was deeply related to your current problem. I'd ask that owner the detail of what was happened.
My speculation is that the person used a jump cable but the polarity was reversed. This often causes a few to several other problems in addition to the open 120A ALT fuse.
My speculation is that the person used a jump cable but the polarity was reversed. This often causes a few to several other problems in addition to the open 120A ALT fuse.
Last edited by YoungNas; Dec 8, 2018 at 11:26 AM.
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From: PA
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Okay so I charged the battery and test it everything looks good, also unplugged the alt120a fuse and repluged it. Now the car started working and the battery is charging around 14.15-14.21V. Hope this time it will stay like this. If anything happened I will tell you guys tomorrow.
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Last edited by YoungNas; Dec 8, 2018 at 04:48 PM.
Lexus Champion
Joined: Sep 2016
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From: AB
one dead cell internally. Charging system problem can be confusing. If you don't exactly know what
tie cause is battery and alternator will start killing each other.
Racer
Joined: Jan 2018
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From: SoCal mtns.
Okay so I charged the battery and test it everything looks good, also unplugged the alt120a fuse and repluged it. Now the car started working and the battery is charging around 14.15-14.21V. Hope this time it will stay like this. If anything happened I will tell you guys tomorrow.
If it goes dead after sitting a few days again do the parasitic draw test.Our cars are NOT good at charging fully dead batteries (claimed),and at least mine isnt.
Edit,I see post#8 posted same thing in video.
Lots of variations,but if 50 ma or less at battery you are good.Many other ways to test each fuse on you tube
Last edited by spuds; Dec 8, 2018 at 07:37 PM.