Functional Requirements for Automotive Multimeters
(1) Measure AC and DC voltage. Considering the allowable range of voltage variation and potential overload, a car multimeter should be able to measure voltage values greater than 40V, but the measurement range should not be too large, otherwise the accuracy of the reading will decrease.
(2) Measure resistance. A car multimeter should be able to measure a resistance of 1M Ω, which is more convenient to use with a larger measurement range.
(3) Measure current. A car multimeter should be able to measure currents greater than 10A, and any smaller measurement range would be inconvenient to use.
(4) Memory maximum and minimum values. This function is used to check for momentary faults in a certain circuit.
(5) Simulated bar display. This function is used to observe continuously changing data.
(6) Measure the bandwidth ratio of the pulse waveform and the closing angle of the primary side current of the ignition coil. This function is used to detect the working condition of fuel injectors, idle stability control valves, EGR solenoid valves, ignition systems, etc.
(7) Measure the rotational speed.
(8) Output pulse signal. This function is used to detect faults in the ignition system without a distributor.
(9) Measure the frequency of the electrical signal output by the sensor.
(10) Measure the performance of diodes.
(11) Measure high current. After configuring the current sensor (Hall current sensing clip), it can measure high currents.
(12) Measure temperature. After configuring the temperature sensor, it can detect cooling water temperature, exhaust gas temperature, and intake air temperature, etc.
