Oscilloscope

It is used to check crankshaft and camshaft sensors, injectors, ignition and network signals. Automotive scopes have presets for common tests. It can capture short glitches. Two-channel or four-channel scopes allow comparing signals, for example crankshaft and camshaft sensors, to check timing relationships. Many workshops use PC-based scopes with large screens. Captured waveforms can be saved and compared later.

It samples voltage many thousands of times per second and draws the waveform.

Comparing with known good waveforms helps pinpoint faults. Correct ground connection is important for clean readings.