How To Check Alternator Voltage With Multimeter. The first test with your multimeter will measure DC voltage indicated with a solid line and a dashed line above a letter V. Connect the multimeter to the positive and negative battery terminals.
To test if the alternator is working well you need to measure the voltage resistance and voltage. How to check the alternator voltage output is one more simple check-up you can do on your own. If you can easily reach to your car alternator then connect red probe of multimeter to alternator positive terminal and black probe to any metal part near it it may a bolt or other thing.
Multimeters come with two probes one red and one black.
Please you shouldnt disconnect the negative battery cable just to test an alternator. With the engine off battery voltage should be between 125 and 128 volts. To check the Higher efficiency at higher rpms even erasing the engine rpm to around 2000 in this cap the rated alternator voltage range is between 132 volts and 148volts. One of the usages of a multimeter is to measure the potential difference or voltage of an electronic circuit.
