PROPER TESTING USING MULTIMETERS
Historically, automotive electrical problems were diagnosed using an analog meter. These meters have been a respectable means for troubleshooting problems but proved to have many limitations. Digital multimeters however, are designed to more accurately detect problems in the components found in today's car and truck computer systems. While analog meters have the potential for changing the test results by interfering with the power to a circuit, the Digital multimeters (DMMs) are less likely to interfere with the circuitry of the vehicle and therefore a more accurate reading can be provided.
The key benefit of a DMM is its multiple functionality. DMMs have the ability to measure DC and AC voltage. But many of today's multimeters include additional functions like:
. Data Recording / Logging
. Frequency Indicators
. Duty Cycle Measurement
. Pulse Width Measurement
. Temperature Measurement
. Current Measurement
It is important when considering buying a meter to know what the meter's accuracy level is and its range of measurement. Many meters are auto ranging - capable of assessing the best range of measurement and making modifications as appropriate. The power level should also be considered; you will want to purchase a meter with a lot of power so that you can keep the DMM for multiple years. Don't be deterred from buying a meter with multiple functions. You will learn to use them as you increase your knowledge of the instrument and will find many of them more beneficial then originally anticipated. When in doubt, ask a colleague or technician in your area for a recommendation.
