Get to Know Your Car Better


OBD Auto Doctor is the advanced OBD-2 software for Windows, Mac and Linux. The software enables you to communicate with your vehicle's On-Board Diagnostic system and turn your computer into a highly capable automotive scanner. OBD Auto Doctor is a must-have tool for everyone interested in getting to know their cars better. Whether you want to monitor data in real-time or reset "check engine" light, this is the only OBD-II software you need!


  • Figure out why the check engine light is on and explore diagnostic trouble codes
  • Monitor fuel economy and get your car ready for emissions test
  • View engine parameter and sensor data in real-time, monitor engine performance

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For gasoline and diesel engines

OBD Auto Doctor works with both gas and diesel engines. The only requirement is that your car is OBD-II compliant.

Supports multiple control units

Depending on your car, you might be able to talk, for example, to transmission controller in addition to the always supported engine controller.

Available in multiple languages

The user interface is translated to the following languages:

English  English  Finnish  German  Hungarian  Dutch  Portuguese  Portuguese Brazil  Czech  French  Romanian  Russian  Slovak  Spanish  Swedish


Diagnostic Trouble Codes and Freeze Frame

Diagnostics Trouble Codes (DTCs) are codes that the vehicle's engine controller unit (ECU) generates when it detects malfunction or other issues. There are three different types of these codes:

  • Confirmed Codes indicate confirmed malfunctioning components. These may require vehicle service to fix.
  • Pending Codes indicate temporary failed components. These don't necessarily imply malfunctioning component.
  • Permanent Codes indicate historic confirmed codes. These will be cleared only by the OBD system automatically.

The codes in all these different types are grouped into four categories:

  • Pxxxx codes relate to powertrain
  • Bxxxx codes relate to body
  • Cxxxx codes relate to chassis
  • Uxxxx codes relate to network or undefined

Freeze Frame is a captured recording of the engine's conditions at the time a malfunction is detected. It can provide valuable information for diagnosing intermittent problems. The Freeze Frame contains:

  • DTC that caused the malfunction
  • Recording of all parameter readings

In addion to reading the generic and manufacturer specific diagnostic trouble codes and freeze frame, you can also reset the DTCs. This will also clear the Check Engine Light. The software contains also offline DTC database for searching and browsing all the trouble codes.

Read: What to do when Malfunction Indicator Light illuminates?

Readiness Monitors

The purpose of readiness monitors to vehicle is to self-test their emission systems. Vehicles perform up to 11 system tests, these are so called readiness monitors. The readiness monitors identify whether the vehicle's computer has completed the required tests while the vehicle is being driven.

Readiness monitors can have different completion status:

  • Ready (green mark) meaning that the test has been completed
  • Not ready (red mark) meaning the test is uncompleted

Note! Depending on your country, OBDII vehicle may not pass the annual inspection unless the required monitors are "ready". For example, the US Environmental Protection Agency guidelines allow up to two monitors to be in a "not ready" state for model year 1996 through 2000 vehicles and one monitor "not read" for 2001 and newer model year vehicles. Now you can check the emission readiness yourself!

Read: Readiness monitors explained

Sensors, Parameters and Graph Plot

Sensors and parameters are what most of you find the most interesting part of the software. You can monitor all the sensor values that your car reports in real-time.

The software updates the values in sequential order as fast as possible. The speed depends only on the adapter. The more expensive genuine adapters will perform faster than the cheap clone OBD2 adapters. In addition to showing the current values, minimum, average and maximum values are provided too.

Some typical sensors include engine coolant temperature, fuel pressure, intake manifold absolute pressure and air flow rate from mass air flow sensor, to list few of them. The software has support for over 110 powertain parameters (PIDs) in the range of $00 - $6F. You can pick the most suitable data reading units; both metric and imperial (English) units are available.

The data graph or oscilloscope can plot any numeric sensor value that is supported. With the OBD oscilloscope, you can visualize sensor value changes easily. Graphs are great tools because they communicate information visually. Even large amount of data, or fast changing data can be interpreted much better when expressed as a graph. Graphs help you to identify sudden spikes and trends in the data.

In addition to visualizing the numeric OBD data, our software enables you to save the graphs to your computer as image files. You can share the images with your mechanics or friends, or you can post them to automotive forums when asking repair advice from fellow DIYers.

Read: The OBD-II sensors and parameters supported by OBD Auto Doctor

Oxygen Sensor Monitoring Tests view

Oxygen Sensor Monitoring Tests

Oxygen sensor monitoring test results provide measurement data from the on-board oxygen sensors. The data include current test values as well as minimum (the minimum value to which the test result is compared) and maximum (the maximum value to which the test result is compared).

This service is OBDII MODE $05 and it may be available only on vehicles using ISO 9141-2, ISO 14230-4 or SAE J1850 protocol.

On-Board Monitoring Tests view

On-Board Monitoring Tests

On-board monitoring test results for Specific Monitored Systems provides access to the results of on-board diagnostic monitoring tests for specific components and/or systems. Examples of these are catalyst monitoring and the evaporative system monitoring. The components and systems are either continuously monitored (e.g. misfire monitoring for gasoline vehicles) or non-continuously monitored (e.g. catalyst system). In addition, this service can be used as an alternative to the OBDII MODE $05 to report oxygen sensor test results.

This service is OBDII MODE $06. It is available for ISO 15765-4 (CAN) too.

Vehicle and ECU Info view

Vehicle and ECU information

Check out ECU name, Vehicle Identification Number (VIN), Calibration Identification (CALID) and Calibration Verification Numbers (CVN). You can allow follow In-use Performance Counter values in this view.

Vehicle Profiles view

Vehicle Profiles

With vehicle profiles you can create separate profiles for all your vehicles. You can, for instance, pick photo and adjust fuel correction factor or engine displacement!

Troubleshoot Console

The console view is targeted for advanced users only. With the console you can troubleshoot problems by sending custom commands directly to the vehicle. Only for those who know what they do!

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