With the ever growing number of modules and systems on the latest vehicles rolling into your bays, we have started to take a look at how we approach the task at hand. What has been the Diagnostic System check as you have come to know it is now being referred to as the Vehicle Level Approach. This idea works hand in hand with the idea of Functional Diagnostics and cars with GMLAN that support it. For more information on those topics, click here.

The Vehicle Level Approach is directly related to some of the recent changes you may have noticed in eSI (for an update on that topic, as well as some other tips and tricks to navigate in eSI, click here) and are part of an effort to streamline the differences between eSI navigation and  how you use the Tech 2. A new section in eSI is the "Vehicle Control System" and can be the new beginning point in any vehicle diagnosis. The illustration to the left shows what can be found in the subdirectories. From here, you can link to the Diagnostic System Check - Vehicle. Now we take you from the traditional  Diagnostic System Check, to a more thorough one that actually polls each module on the vehicle. Doing this gives the technician an entire view of what is going on in the vehicle as far as DTCs and modules not communicating. On many newer vehicles that support the "Computer/Integrated System Check", this will involve the use of a CANDI module along with the Tech 2. On vehicles that do not support the "Computer/Integrated System Check", you would use the Class 2 DTC check and/or Message Monitor that you may be familiar with. Either way, the principle is still the same, take a look throughout the car and get a more complete picture of what might be wrong. If your results show a lack of communication with a module, linking over to the "Data Link References" page will get you to charts needed to address this concern. If you have good communication but a DTC has been found, your next step would be to link to the "Vehicle DTC Information" page.
  A new innovation of eSI is the "Vehicle DTC Information" link (highlighted above). Clicking on the link will give you a list of ALL of the possible DTCs that your particular vehicle could set AND their descriptors. Another plus is a hyper link that will take you to the chart. From there your diagnosis would continue.
  What if (there is always a What if) you had good communication and no DTCs, simple click on the "Symptoms" link to take you to a page with each symptom chart broken down by section.
The illustration to the left is a great example of what we mean by "Vehicle Level". Notice that the links all end in - Vehicle. The attempt here is to no longer look at the vehicle system as something separate from the rest of the car as we need to take a look at the vehicle as a WHOLE! Keeping this thought in mind and applying what we have done with the Strategy Based Diagnostics in the past, will give you a good  map to use when you travel down the diagnostic road. Having access to the entire vehicle's different diagnostic charts from one area is just another plus to getting the car fixed right the first time.