In this cases,first inspect your car battery.Either battery terminals are dirty or not connected properly or battery charge got less. Less that 12 volts.
In most cases if the battery light is coming its not a bad battery but instead a failing alternator and in most cases the alternator will continue to charge but not allow the light to go off. If the PCM (computer) see the voltage on the yellow wire is below 4 volts or above 12.4 volts, it will turn the battery light on. If you are replacing the alternator then be sure to use the factory OE Ford alternator because after market alternators do not perform right and you will in most cases still have the battery light on.
In most cases the alternator will still charge ok but it can not turn the light off with the correct voltage to the PCM (computer) .If the PCM (computer) see the voltage on the yellow wire is below 4 volts or above 12.4 volts, it will turn the battery light on.
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In most cases if the battery light is coming its not a bad battery but instead a failing alternator and in most cases the alternator will continue to charge but not allow the light to go off. If the PCM (computer) see the voltage on the yellow wire is below 4 volts or above 12.4 volts, it will turn the battery light on. If you are replacing the alternator then be sure to use the factory OE Ford alternator because after market alternators do not perform right and you will in most cases still have the battery light on.
This will help.
Thanks.
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