# Diagnostics

- User presets
  Preinstalled operating modes of the USB Autoscope II.
- Waveform library
  Typical waveforms.
- Engine management diagnostic techniques.
  - Ignition systems diagnosis
    How to make connections for diagnosis and descriptions of common ignition system malfunctions.
  - Plug-In "Time parameters"
    Automatic calculation of duration of a pulse, duty cycle and frequency of a signal.
  - Plug-In "Measurement of ignition advance"
    Measuring timing advance.
  - Lambda-probe
    Diagnosing voltage waveforms from Oxygen sensors. Examples of good and bad waveforms for various sensors.
  - Mass Air Flow (MAF) sensors
    Techniques for diagnosing MAF sensors. Examples of good and bad waveforms for various types of MAF sensors are included as well.