A generic emissions scan and a manufacturer-specific diagnostic session do not necessarily expose the same controllers or functions. Missing coding menus or body-system data may reflect tool coverage rather than a fault in the car.
Check the intended capability
Keep the tool version, vehicle identification and name of the function requested. Confirm coverage through the tool supplier’s documentation for the actual model and system. A successful basic code read does not establish support for every service routine.
If another workshop has obtained more detailed information, ask for its complete report. Avoid buying a controller because one reader cannot access a menu. Conversely, do not dismiss a genuine communication fault solely because generic engine data remains available. Explain which modules can and cannot be reached, and whether the issue began after vehicle work or a tool update. That distinction helps determine whether the next step concerns the interface, access requirements or the vehicle itself.
Related help
- Diagnostic Socket Has Power but the Scanner Will Not Connect
- Vehicle Network Fault Appears When a Trailer Is Connected
Browse all fault guides or use the vehicle module finder to prepare your enquiry. Send your vehicle details, what has gone wrong and any scan or test results. Contact us before booking or posting a module so we can check whether we can help.