Why You Should Save All Your Diagnostic Data


Manage data 2


What do you do with diagnostic data such as control modules’ log files, freeze frame data, PID’s, system calibration data, scope captures, and historical fault data, among others, when you are done analysing it? Have you ever considered saving all of it for your own future reference, or do you delete all of it, and start your next diagnosis from scratch? In today’s highly competitive environment, you need every advantage you can get, and while having an archive of reference data represents a huge advantage over your colleagues, saving all your diagnostic data can be a daunting task if you go about in the wrong way. Thus, in this article, we will look at ways to archive your data efficiently, starting with this question-

What types of data should be saved?       

The short answer is, save as much as you can. You probably do not always think about it, but depending on the nature of the problem, performing a test drive with a scan tool or oscilloscope connected to the vehicle generates huge amounts of useful data- all of which might help you diagnose similar issues on a similar vehicle in the future.

For instance, diagnosing shift issues on an automatic transmission can be difficult at the best of times, and even more so when you have to replicate the operating conditions under which the fault, failure, or malfunction first appeared. Thus, if you have a multi-channel oscilloscope and you set it up correctly you can record as many operating parameters as you have channels for, such as engine temperature, freeze frame data, engine speed/load, road speed, actual shift points, torque converter lock-up clutch operation, throttle openings, and others.

Similarly, if you are diagnosing say, a random misfire code, you can use a multi-channel oscilloscope on a test drive to record engine temperature, freeze frame data, fuel pressure, fuel trim values, injection timing relative to ignition timing, ignition coil ramp-up and discharge times/waveforms, and as many other pertinent operating parameters as you have channels on your oscilloscope for.

Recording as much data as is possible will accomplish two very important things. The first is that you will have a more complete picture of what was happening when the fault occurred than you would have had had you performed a static test in the workshop. The second is that you now have a complete record of what was happening in relevant systems when the fault occurred, but not only that- some of the waveforms/graphs/data you now have will be KG (known good) data, and some will be KB (known bad) data. Of course, which data is bad vs. which is good largely depends on the nature of the problem, the make/model/year of the vehicle, and in some cases, variables like environmental factors.

If you are an experienced technician you very likely know all of this, but for the purposes of this article, that is beside the point. The actual point is this; if you retain the data you'd obtained in real-time, you have data that you can share with the customer, colleagues, your supervisor (if needs be), and thousands of technicians in other parts of the world, which begs this question-

Why share diagnostic data?

The internet is not only a wonderful thing- it is also a very useful thing because it accommodates specialised technical websites like mechanic.com.au, iATN.net, Pico, and others that specialise in the exchange of information among technicians the world over.

This last point is particularly important in the Australian context, given that car manufacturers here do not share technical or diagnostic information with the independent repair trade.  Therefore, sharing data with other users on these websites and their discussion forums can accomplish two things. The first is that someone, somewhere, has encountered the problem you are struggling with before and has posted an effective and reliable fix or remedy for it. The second thing is that by posting your data and your fix, you may help a technician in another country fix a problem he has never encountered before.

Nonetheless, before you can share data you have to save it, and it is here that things can become a bit complicated. You can, of course, save your data directly to your scan tools' hard drive, but the storage capacity of most scan tools is rather limited, and besides, retrieving specific data stored on a scan tool is often difficult and time-consuming. You could also save data to external devices like flash drives and external hard drives, but the problem with this is that scan tools typically save data in formats such as “.scm” or “.vsm”, and many others that cannot be read by (especially) Windows computers, tablets, and smartphones.

Therefore, to get around the “Windows Cannot Open This File” issue, you need to convert proprietary scan tool file formats/extensions to formats and/or extensions that Windows can open. Such file converters do exist, but in this writer’s experience, the useful ones are never free, or when they are free, they can convert only a limited number of file formats, and then badly, at that. However, there is an exception to this- a little-known file converter published by Snap-On Tools, known as-

Shopstream Connect®


Image source: https://www.snapon.com/diagnostics/us/SSC

Before we get to specifics, it should be noted that although the Shopstream Connect® software does not support all scan tools, it does support a wide range of scan tools, including all of the following-

ETHOS family of scan tools

  • ETHOS+
  • ETHOS Tech
  • ETHOS Pro
  • ETHOS Edge

SOLUS family of scan tools

  • SOLUS Ultra
  • SOLUS Edge

MODIS family of scan tools

  • MODIS Ultra
  • MODIS Edge

VANTAGE family of Scan tools

  • VANTAGE Ultra

MICROSCAN family of scan tools


Essentially, and according to Snap-on Tools, the [free] Shopstream Connect® software provides users with a “practical in-shop software tool to transfer, save, manage, review, annotate, e-mail and print files that were saved or recorded on your Snap-on [or other supported] diagnostic platform”. Put simply, if you download and use this software, you can store all of your diagnostic data in a location other than on your scan tool.

As a practical matter though, "diagnostic data" can include anything from simple multi-meter readings to pictures of broken parts/components, to complex multi-channel oscilloscope captures -both still and moving. Moreover, the Shopstream Connect® software allows users to choose how they want to view data. For instance, you can choose how many PID’s to display, you can change and adapt not only background colours but also the thicknesses and colours of scope trace lines, as well as zoom in or out of any part of any display. 

Most importantly though, the software also backs up your scan tool and allows internet communication with diagnostic share sites* like iATN.net, or Diag.netto obtain second (or sometimes, third) opinions on your findings, or to up/download scope captures and/or other diagnostic data.

* Although Pico also offers free oscilloscope software and maintains what is arguably the most comprehensive waveform library on the internet, Pico oscilloscope files are made and stored in Pico’s proprietary “.psdata” format, which means that only Pico software can read and open these files. However, both Diag.net and iATN.net have made it possible to upload .psdata files to their sites via email and/or Skype in recent years.

Now that we have a better idea of what is possible to save, we need to discuss how to actually save data in ways that will not overwhelm you in very short order, so let us start with-

How to organise your data

Organise data


While your stored data can help someone on the other side of the world diagnose a tricky issue, the primary reason why you would want to save diagnostic data is to create a reference source/library for your own use. Such a resource will not only save you a lot of time- it will also make you more efficient in diagnosing faults.

So let us assume that you have a scan tool that is compatible with Shopstream Connect® software. If our assumption is correct, you can now download all the data that is stored in the tool to a Windows-based computer, but before you do that, you need to develop a naming scheme for your files; if you don’t, you will almost certainly never find anything you are looking for after a few months.

The problem is this: you will be saving different types of diagnostic data, but if you open a folder for every type of issue that you ever deal with on every vehicle, you will very soon have thousands of folders. In practice, this is just as bad as having none when you are looking for say, repair notes on a manufacturer specific code on a particular vehicle.

Unfortunately, there is no single file naming scheme that will always work for everyone, but this writer has developed a system that might work for most people most of the time. Here is how it works-

Create parent folders

The guiding principle when you create an archive of this nature should always be to aim for maximum ease of use. There is no point in having an archive if you can never find anything in it, so start off by creating a parent folder for each make of vehicle you work on. Limited space prevents the inclusion of relevant screenshots here, but let us use Ford as a practical example.

So you create a folder, name it FORD, and save it to a convenient location or directory. Next, you create a dedicated sub-folder that you can name say, Ford F-150 Scope Captures, into which you can load all Ford F-150 scope captures. However, when you name a scope capture file after a repair, be sure to start the file name with the make, model and year, then the fault code and one or two key symptoms, followed by KG for “Known Good” or KB for “Known Bad”, or, “Undetermined”. You can then add something like "Capture 1", "Capture 2", etc. if you have more than one capture for that fault.      

The first trick is to have as much information as possible as early as possible at the start of the file name to prevent you from having to click on a file to see its full name. The second trick is to be consistent when you name files because if you cannot find a particular file quickly, you can use Windows' Search function to find it simply by typing in the first two or three words of the file name into the search box. If you are not consistent, you may have to type the entire file name into the search box, but this only works if you can remember what and how you had named the missing file.

Similarly, you can create sub-folders for all the Ford models you work on. Thus, if you want to see a scope capture for say a 2005 Ford F-250 with a misfire, you only need to open the Ford parent folder, look for the relevant year and model, and from there, navigate to the relevant fault code. From there, it is a simple matter to navigate to the “Known Good”, “Known Bad”, or "Undetermined" sub-folders that will contain all your saved oscilloscope captures that pertain to Ford F-250 trucks with misfires caused by the fault code(s) you'd extracted. 

At first reading, this scheme might appear to be cumbersome, but once you get the hang of it, you can find any saved file for any vehicle make, model, and year within a few seconds with only a few mouse clicks. The most common alternatives this writer has seen involves having to scroll through folders containing thousands of scope captures or other data sets with names like “Ford Mode 6”, “Mazda ABS (insert code here) Data”, and other equally random or nonsensical names.

It may be true that people who randomly name files know how to find what they are looking for in their own archives. However, if you are just starting to save your own diagnostic data for future reference, you would do well to devise a file-naming system that does not cause you to spend more time looking for saved files than it would take to diagnose an issue from scratch, which leaves us with the question of how to make-

How to make data transportable

Lugging a laptop computer around everywhere you go is impractical, so the obvious answer is to transfer all or some of your archive files to a smartphone or tablet for use on the go, so to speak. There are various ways of doing this, but the easiest and most effective way is to use a synching app but take note that while there are many free apps available they are not created equal, and you may have to research the various available options to find one that suits your needs.

Nonetheless, apps like these allow you not only to transfer your files to almost any portable device from your computer but also to share files with other devices via various communication platforms. At a minimum though, your chosen app should allow you to retrieve saved diagnostic data with a smartphone or tablet from remote locations- such as from your computer or storage in the cloud.

If you are tech-savvy, you will no doubt recognise the need to save your data to several locations and/or external devices on a regular, if not daily basis. Equipment failure can happen at any time, so wouldn’t you just hate it if you spend years building up an archive of reference data only to lose all of it due to a sudden, catastrophic hard drive failure?    


Having access to your own reference data or waveform library can be a real lifesaver, so it seems somewhat strange that so few professional technicians go to the trouble of collecting, sorting, and archiving all the free diagnostic data they generate every day. Nonetheless, we hope that this article has inspired you to create an archive of reference data for your own future reference. You may not do it today, but when you do, you will be very glad that you did when you can reference say, waveforms that you know nobody else has, or has access to.