How To Check Alternator By Disconnecting Battery. If youre tempted to test an alternator by disconnecting the negative battery cable dont do it. If disconnecting the battery interferes with the voltage regulators control voltage input its possible for the alternator voltage to go way over the top Ive heard some say.
In the pre-computer days you could pull it off without damaging anything. But in case the engine continues running even after disconnecting the battery then it means the alternator is perfectly okay. A good alternator may indeed keep the engine running but it was never a good test.
For an alternator that stops working suddenly the brushes may be worn out.
In the pre-computer days you could pull it off without damaging anything. The faulty alternating device needs to be disconnected from the dead car battery and removed from the serpentine belt. If the vehicle continues to run your alternator is properly charging the battery. In the pre-computer days you could pull it off without damaging anything.
