This needs testing.
Any automotive parts store can test your battery, and most can check charge output with the same meter.

What you are looking for is 13.5 to 14 volts with the engine running.

A cheap volt meter from radio shack will work.

Your issue may simply be a bad battery to body or body to transmission bell housing GROUND connection, clean, replace or tighten as needed, then retest your system.


Have a great day.

__________________
ASE Master Mechanic

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