Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostics concept: Bus
The bus configuration can be read and reset as before. Now, besides "Missing" and "OK", there is also "Added" if the unit has been mounted without resetting the bus list. Furthermore, "Not fitted" is displayed for control modules that are not present and should not be fitted in the car. The bus list is divided into four pages, two for the I-bus, one for the P-bus and one for the O-bus.
An automatic list update occurs when adding or removing a control module with "Add/Remove". All buses are checked according to previously defined concepts in connection with DTC reading. Yet another aid has been added for bus fault diagnosis; a fault counter in each control module can be read and reset to zero with the diagnostic tool. The counter value increases during short-term interruption to the control module in question.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.