Battery gauge jump to high side
CHECK ALL BATTERY CABLES..CHECK ALT FOR CHARGING SUCH AS A BAD DIODE
New battery and new alt
Battery and alt are brand new
Test the voltage at the battery with engine running. This voltage should be somewhere between 13.5 and 14.7 volts. If it is higher than that the alternator is overcharging and the cause needs to be found.
Which would be the voltage regulator in the alternator.
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