How to Check an Auto Battery Voltage With a DMM
- 1). Turn on the digital multimeter. Switch the scale setting to "Volts DC."
- 2). Place the black (negative) multimeter probe on the negative battery terminal. Place the red (positive) multimeter probe on the positive battery terminal.
- 3). Look at the multimeter readout; the voltage reading should be approximately 12.6 Volts DC.
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