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Testing For Current

Current Test:




To test for current the meter must be connected in series in the circuit. Current measurements always involve a component being removed or disconnected from the circuit. The circuit current flows through the meter, which displays the current in amps or milliamps. The meter should have a rating higher than the expected current.

NOTE: Never use a meter set on a current scale to measure voltage. Severe damage to the meter, the circuit, or both will result.

Two commonly used locations for taking current measurements are at a fuse and at the battery.

To measure current in a Windshield Wiper Motor, for instance, the meter should be connected across the fuse terminals, after removing the fuse. The meter can be inserted in any circuit where a single circuit can be temporarily opened to make the measurement.

A special use of current measurement is the case of a vehicle whose battery goes dead with no explanation. In this case, refer to the Current Drain Test in Battery Starting and Charging. Starting and Charging