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Overcharging Alternator

SCR34M3R

By SCR34M3R,
in General Maintenance

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SCR34M3R Rising Star

SCR34M3R

Posted
Posted (edited)

hay guys

i will start from the beginning, i put a stereo in my car (R34 sedan) over the weekend, and when i was tuning it i didnt start the car, which ended in a flat battery, so we push started it. battery is fully charged again but when car is running it shows 15.8volts which i was told the alternator is overcharging.

has ne one got ne ideas how to fix this? or do i just buy a new alternator?

Cheers

Edited by Raistlin
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grim32 Community Regular

grim32

Posted
Posted
hay guys

i will start from the beginning, i put a stereo in my car (R34 sedan) over the weekend, and when i was tuning it i didnt start the car, which ended in a flat battery, so we push started it. battery is fully charged again but when car is running it shows 15.8volts which i was told the alternator is overcharging.

has ne one got ne ideas how to fix this? or do i just buy a new alternator?

Cheers

First i would try turning off all the stereo, amps etc etc and see if it charges at the correct rate, 14.1 when cold and about 13.6 volts when warm.

The reason i say this is because you may have tapped into the voltage sence wire somehow so the alternator thinks the battery is low on voltage and will throw out a higher rate of charge.

SCR34M3R Rising Star

SCR34M3R

Posted
  • Author
Posted
First i would try turning off all the stereo, amps etc etc and see if it charges at the correct rate, 14.1 when cold and about 13.6 volts when warm.

The reason i say this is because you may have tapped into the voltage sence wire somehow so the alternator thinks the battery is low on voltage and will throw out a higher rate of charge.

just tryed that didnt change but it is sitting at about 15.48-9volts with battery light on all the time

d00dz Grand Master

d00dz

Posted
Posted

It seems that on my PFC the battery volt is approx between 14.8-15.3.

I havent had any problems with the car's electrics or anything.

Would this be an issue? Alternator? Battery?

Also it seems as though when I turn on my headlights the voltage drops approx 0.5-0.9volts. Hmmmz..

700HP-GTR33 Mentor

700HP-GTR33

Posted
Posted
I have seen batteries explode...get it fixed by an auto elec.

As in explode in the engine bay ;) .

Take it serious if you don't want things to melt ...stop messing with it and get an auto elec....please,

your killing me. :P

tridentt150v Grand Master

tridentt150v

Posted
Posted

Get your battery checked, if it has a faulty cell you will have an open circuit. The alternator thinks it is charging a flat battery so max's the voltage.

BTW your battery will not hold a good charge if this is the case.

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