Alternator problem need help
12-07-18, 11:58 PM
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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.
12-08-18, 02:35 AM
#2
Racer
Get a full charge on the battery with a charger.Then see what you have.
12-08-18, 02:37 AM
#3
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It would be better to inform us why you needed to replace the 120A ALT fuse. Did you use a jump cable?
12-08-18, 02:56 AM
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and No I didn’t use a jump cable.
12-08-18, 02:58 AM
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12-08-18, 05:13 AM
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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.
12-08-18, 10:20 AM
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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; 12-08-18 at 11:26 AM.
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12-08-18, 11:57 AM
#9
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How old is the battery? Did this situation just develop? Definitely have the battery checked.
12-08-18, 12:19 PM
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12-08-18, 02:43 PM
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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.
12-08-18, 04:28 PM
#12
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How did you hold the 120A ALT fuse when you re-plugged it? Did you use correct screws?
Incorrect screws may cause the Galvanic corrosion problem.
Incorrect screws may cause the Galvanic corrosion problem.
12-08-18, 04:37 PM
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Last edited by YoungNas; 12-08-18 at 04:48 PM.
12-08-18, 05:30 PM
#14
Lexus Champion
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.
12-08-18, 07:32 PM
#15
Racer
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; 12-08-18 at 07:37 PM.