Introduction to 4 small functions of multimeter
(1) Frequency test
As long as the sensor can produce a frequency signal, it can be frequency tested with a multimeter. Such as intake pressure sensor and knock sensor, etc. Make full use of the frequency test function of the multimeter to test the working status of the frequency signal sensor and determine the performance of the sensor.
(2) Test of duty cycle
Duty cycle is the percentage of a signal's operating time to the total time. Use a multimeter to test the duty cycle of components such as the idle speed control valve that adopts the duty cycle control method to determine whether the idle speed control valve does not act, acts, or acts inaccurately.
(3) Measurement of closing angle
Measurement of the closing angle can reveal ignition-related causes such as distributor contact spacing and distributor mechanical wear. The method is as follows: ① Insert the black test lead into the COM jack and the red test lead into the corresponding jack at the closed corner. ② According to the measured number of engine cylinders, set the function switch to the required "DWELL" range. ③Connect the black test lead to the iron or negative terminal of the battery, and the red test lead to the low-voltage terminal of the distributor or the negative terminal of the ignition coil. ④Start the engine and the closing angle can be read.
(4) Make good use of special functions
Some automotive multimeters have some special functions. For example, some multimeters have analog conversion modules (referred to as conversion modules), which have the functions of simulating sensor signals and driving actuators. If these functions are used properly, the efficiency can be greatly improved.
Multimeters can also play many other roles in maintenance, and there are still many to be discovered in practice. Only by continuously expanding and adopting new application methods in repair work can maintenance efficiency be improved.
