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Sudden Voltage Drops

854 Views 3 Replies 4 Participants Last post by  Jayare
In the summer when my car's huge fans are trying to cool down the engine and the AC is running as well, some times the voltage drops and an Orange light pops in the panel. I have to quickly switch off the AC and dim the lights to conserve energy .... if i switch off the car shortly after that the battery goes dead and cant start. The same happend last summer and then it didnt happen again until now when the heat wave is back.

I have tried to get the battery changed but the voltage seems to be fine. Is it my generator not making enough power for the car or shall i try to change the battery which is behaving pretty normal.
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One more step you can take as well if you have a volt meter. More than likely, it is your voltage regulator (less than $40 at NAPA) that has gone south. It is very seldom that the alternators on our cars go out. Check your voltage at the battery with the car off. It should be a tad above 12 volts. With the car running, again check at the battery and you should be reading near 14 volts.

The regulator is very simple to change out as it's held in by two phillips screws on the back of the unit. I did mine in about twenty minutes and found it easier for me to jack up the car and do the R/R from the underside.

Good Luck,

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