# Brake and battery light stay on



## gune562 (Feb 10, 2010)

hey guys, my girlfrends car has this electrical problem that the brake and battery light on the cluster stay on. This problem has been seen in the past and figured it was the alternator since the battery would die out shortly after. She has gone through two alternators in the last two years. we recently installed a new one 4 months ago and again the lights flicker on and off. When this is happening the headlights get brighter and the fan blows harder......
Any suggestions would be greatly appreciated. 
thanks
sal


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## pulsar86 (Aug 13, 2009)

Check the alternator with a multimeter at the battery posts a good alt will put out between 13.6 and 14.3 volts at idle with accessories etc off. Also check and clean all earth points before checking alternator output, bad earths can cause charging problems [and warning lights] as well.


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## gune562 (Feb 10, 2010)

thanks pulsar,
I cleaned the post on the battery and checked the voltage potential across the terminal and got 16.5v at idle and 18.5v at 3k rpms. I noticed that the battery kept fizzing after I turned off the power. What could be causing such a high voltage at the battery?


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## joe_yoh (Feb 9, 2010)

That is an alternator prob, maybe.


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## dreamteam (Jul 29, 2005)

Oh, Oh...the old fizzing battery trick. You definitely have a stuck voltage regulator inside that alternator. Go get a replacement alternator quick, before you completely fry the battery.


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## kizer24 (Mar 23, 2008)

Does she lose oil pretty quick? She could have a oil leak at the front seal. Sprays the alternator with a fine mist that clogs up shit quick.


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## TOOQIKK (Jul 11, 2009)

definately the alternator.....the voltage regulator and diodes love to go bad.....


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