Auto Diagnosis & Training Software

Scan Tool Companion Car Diagnostic Training Software

A Quick Reference Guide to Onboard Diagnostics II
for use with ANY scan tool or scanner software
scan tool companion software main menu

Last Updated July 2015

If you have a scan tool or scanner software, you need this diagnostic guide!





Scan Tool Companion is a quick reference guide for ALL scan tool users.

This program provides guidance and help on how to troubleshoot Check Engine Light problems, Trouble Codes, and drivability, emissions,
and performance problems on 1996 and newer OBD2 vehicles with a scan tool.

This software does NOT interface with your vehicle. Rather, you use it with your scan tool or scanner software to better understand and use the information your scan tool is showing you. Scan tools read codes and display all kinds of data. But they do not tell you what to do with that information. That's where this product helps. If you have a code or a symptom, Scan Tool Companion can help you figure out what the problem is, what might be causing it and what other diagnostic tests or checks might be needed to nail down the problem.

For example, say your Check Engine light is on and you have a P0171 or P0174 lean code. Now what do you do? The code does not tell you what to check or what to replace. The code only tells you the engine has a lean fuel problem. So you open the Scan Tool Companion program on your PC or laptop, click on the button for the code(s) you found, and Scan Tool Companion gives you a list of POSSIBLE CAUSES, and tells you WHAT TO CHECK and HOW TO CHECK IT. Is that cool or what? This is the kind of information that can help you fix your problem correctly the first time without having to blindly replace a bunch of parts and hope that one of them fixes the fault.

FEATURES include:

* Diagnose problems by Symptom, By Code or by System.

Scan Tool Companion tells you the most likely causes of symptoms or codes, tells you what to check, and
what PIDS (data parameters) you need to look at with your scan tool to identify the fault.
It also offers expert tips on what parts might need to be replaced and why.
It's like having an expert technician at your fingertips to help with your diagnosis.
This kind of guided diagnostics is only available in the most expensive professional grade scan tools.
There is even information on Mode 06 diagnostics, what it is, how to access it and how to use it.

* Saves you time, frustration and replacing parts unnecessarily!

* Help Sections help you better understand the basics of your vehicle's onboard diagnostic
system (OBD II), including what it does, how it monitors various sensors and systems, and why it sets fault codes.

* Tips on how to pass an OBD II "plug-in" emission test (what's required, what they look at, what to do if your vehicle is rejected or fails).

* Quick reference sections on basic sensor operation, fuel injection, ignition and emissions.

* A quick reference list of common generic "P0" fault codes .
Please note this program does NOT include "P1" manufacturer specific enhanced codes.
Most scan tools will give you a code definition for P1 codes if its data base includes your vehicle.

Sample Screens from the Scan Tool Companion program:
(Click on the image to view the full sized screen capture:)

fuel diagnostics screen . . rough idle diagnostics screen

engine control system screen . . engine misfire diagnostics screen

oxygen sensor and catalyst diagnostics screen


NOTE: This program does NOT interface with your vehicle or make your PC function as a scan tool.

This program is designed to provide guidance so you can make better use of your scan tool to diagnose and repair faults.

The BASIC and ADVANCED diagnostic tips tell you which PIDS you should be looking at, and what kinds of problems can set various codes.
You can look up MOST LIKELY CAUSES of faults by SYMPTOM or CODE.

System Requirements:

Program requires Windows XP, Vista, Windows 7, Windows 8 (Win 8 for desktop but NOT Win 8 RT for tablets), or Windows 10.

Please Note: This software will NOT run on an Apple/MAC computer, ipad, iphone, Android smart phone or tablet unless you have installed a "Windows Emulator" utility program that allows Windows programs to run on such devices..

PRICE: $39.95 for download version (add $3.95 postage for CD version - US buyers only.)

Please Note: No Refunds on Software

Click HERE for Tech Support if You Are Having a Software Installation Issue


Scan Tool Companion quick overview video:


NOTE: If the video link below is not visible, click on the safety bar at the top of your internet browser to "allow blocked content" (links & script) so you can view the video:




How To Order Scan Tool Companion


<<<< Click the BUY NOW Button to purchase the Scan Tool Companion download for $39.95.

The program will be sent to you as an email ZIP file attachment when we receive notice of your credit card payment from Paypal. Please note that orders are processed manually. If you place your order late at night or on holidays, it may not be processed until next business day.

For Download help, click here



To order SCANTOOL COMPANION on a CD (Domestic orders only, No International Orders for CDs), Use the button below:

<<<<< Click the BUY NOW Button to buy Scan Tool Companion on a CD for $39.95 plus $3.95 postage.
Allow 3 to 5 business days for domestic mail delivery.


Sorry, No International Orders for CDs. Domestic only. If you are located outside the U.S., please order the download version (see above).


Click Here if you wish to order Scan Tool Companion by mail (printable order form)


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