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Q: What causes my positive battery terminal to turn black?

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Twice in 4 months I've had to replace my positive battery terminal because it turned black & quit

A: The black colored surface on the battery te...

The black colored surface on the battery terminal is caused when a battery releases hydrogen as it charges and discharges. This creates a lead oxide that will eventually build up enough to create a low current path to ground that may eventually cause it not to transmit power properly. Chances are that if the terminal is turning black like this, your battery will soon be going dead as well. I would recommend having the battery tested to see if it still maintains the proper amount of power.

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