That&#x27;s a slightly differnet scenario, as the disgnostics don&#x27;t actaully &quot;fix&quot; anything, although you can use disgnostics software to adjust settings like ride height, injector settings etc. There really was no extra work involved by the manufacturers in the link you provided, they had all the information well documented and just refused to publish it.<p>There is a downside to diagnostics tools being freely available, you can clear any fault codes before you sell the car to an unsuspecting buyer, this will prevent the dash warning lights appearing until the sensor registers the fault again, which could be under particular driving conditions. Of course, this is little different from the normal &#x27;buying a used car&#x27; pitfalls.<p>ON the other hand, I saved literally thousands of dollars by diagnosing my air-suspension fault myself, and then carrying out the work required based on that fault code. Pretty sure the dealership don&#x27;t want me doing that, but then maybe they shouldn&#x27;t charge a high hourly rate for a 5-10 minute process of attaching a cable and looking at the screen?