PURPOSE: To read the number directly and to make the number easy to see, by incorporating an advance meter together with a tachometer and a voltmeter in one equipment, and using a common digital system for displaying the measured values.

CONSTITUTION: An automobile tester is constituted by a digital display part 1, which displays the measured values, a switch 2, which changes the measuring items of a tachometer T, an advance meter A and a voltmeter V, a power source cord 3 and a plug sensor 4. Thus the switch 2 for changing three kinds of the measuring items is appropriately switched, and the numerical values of the applicable measurements of meters are displayed on the digital display part.