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1998 Dodge Car 3.3L Replaced alternator, low voltage when lights/fans are on HELPPPPP?

Is this a computer problem and which one TCM BCM PCM regulates this? Thanks

Public Comments

  1. one thing you should always remember about new parts is that there is always a chance that they could be defective from the factory. if you replaced your alternator because it wasn't charging properly anymore and didn't recharge the battery before installing it you could have burned out your new alternator, you never recharge a battery off the alternator, check your battery with ignition off, should be minimum 11.75-12v, now start the vehicle and check the battery, it should read 13.75-14v if the battery is not reading at those numbers, your alternator is not charging and you have to replace it. just remember, charge your battery first or if you can replce it new with a new alternator, now you don't have to worry about the low voltage anymore. p.s the voltage regulator is inside the alternator so if thats the problem the alternator would have to be changed. thats what regulates the voltage charge.
  2. the charging system is very easy to understand and diagnosis. if you replaced the old alternator with the same amp output (it should be 130 amps) you should have no problems. voltage at the battery should be 14.7 above idle with major accessiores on. if not look at the voltage regulator this will control the voltage output not the computers. also check all of your grounds. people tend to overlook these but electrity needs a good ground hope this helps