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Oscilloscope Patterns and Waveforms




ABS / ASC / DSC Speed Signals
The Anti-lock Braking System (ABS)/Automatic Stability Control or ABS/Dynamic Stability Control (DSC) control unit process wheel signals received from the rear speed sensors and transmit them to other parts of the overall system (e.g. Digital Engine Electronics, instrument cluster).

Waveform:






Processed Wheel Signal Rear Left And Rear Right
Explanation
A rectangular signal with 50% pulse duty factor must appear on the oscilloscope as a specified curve. The voltage level depends on battery voltage, approx. 10 volt. The duration depends on the speed at which wheel is turned. The signal curve illustrated corresponds to a speed of approx. one revolution per second.