a3c Safety Rules
Version of 27 September 2026.
These Rules are a mandatory part of the a3c End User License Agreement and the established rules of use of the app. If harm results from a breach of these Rules, the user is responsible for it (Art. 1098 of the Russian Civil Code, Art. 14(5) of the Russian Consumer Protection Law). In the EU, a breach of the Rules is taken into account as contributory fault of the injured person.
Writing changes how the vehicle works. Backup, verification and rollback reduce the risk but do not remove it.
1. Mandatory conditions for writing
- The vehicle is stationary and not on a public road. The selector is in P (neutral on a manual gearbox) and the parking brake is applied.
- The engine is off and the ignition is on. If a procedure requires the engine to run (for example, DSG clutch adaptation), the app will tell you when to start it. Never run the engine in an enclosed, unventilated space.
- The on-board voltage is at least 12 V. Connect a battery charger with a power-supply (voltage maintenance) mode. Jump starters (boosters) are not suitable for this.
- The vehicle is yours, or you have the owner's consent.
- The adapter works properly and suits your vehicle. Cheap ELM327 clones may drop commands and corrupt control-unit responses.
2. Before writing
- Connect your Mac to mains power and disable sleep.
- Plug the adapter firmly into the socket. The cable must not be under tension. For Bluetooth and Wi‑Fi, keep the Mac close to the car.
- Close other programs that use the adapter.
- Switch off unnecessary consumers: lights, climate control, heaters, infotainment.
- Read the function's description, status, warnings and conditions. Check the model, the control unit and its software version.
- Make sure a backup has been created (the "History" section).
- For SFD-protected control units, obtain the token in advance: it is valid for a limited time.
3. During writing
- Do not switch off the ignition, disconnect the adapter, quit the app or let the Mac sleep until the app reports completion.
- Do not touch the controls unless the app asks you to. Follow its instructions (switch the ignition on or off, press the brake pedal) only when it asks.
- Do not run other diagnostic programs at the same time.
- Faults and warning lights may briefly appear on the instrument cluster while writing. Do not interrupt the process because of them.
4. After writing
- Check the result: the verification read in the app and how the function works on the car.
- Read the fault codes. If new faults appear, roll the change back.
- If the app asks, switch off the ignition, wait for the control units to "go to sleep" and check again.
- If you are not happy with the result, roll the change back in the "History" section.
- Keep backups and do not delete the operation history.
- Before driving, make sure the lights, DRL, signals and warnings work as the law requires.
- When selling or handing over the vehicle, tell the new owner about the changes made.
5. Never
- Never write while driving or on a public road.
- Never work on someone else's vehicle without the owner's consent.
- Never start writing at a voltage below 12 V or if you are unsure about the power supply.
- Never use a faulty adapter or work with an unstable connection.
- Do not write values you do not understand. Do not repeat a failed write over and over.
- Do not use the app to change the mileage or to interfere with the immobiliser or airbags.
- Do not disable safety-relevant functions where the law prohibits it.
6. Function statuses
| Status | What it means | How to treat it |
|---|---|---|
| Verified on the car | The write has been performed on at least one car | The result on your car may differ: check the equipment and software version |
| Map found ("map known"), MQB map, unverified, with a caveat | The address and value are known but have not been written on a car, or were verified with reservations | Experimental function, used at your own risk. Make sure a backup exists and be ready to roll back |
| Read-only | The app writes nothing | Control units are not changed |
| Needs research, unavailable | No ready-made write exists | Cannot be applied |
Any status other than "Verified on the car" means the function has not been verified on a car without reservations.
7. Law, roadworthiness inspection and warranty
- You are responsible for ensuring that the vehicle complies with the road traffic rules and the technical condition and roadworthiness requirements of your country. Example for Russia: in daylight, a moving vehicle must have its dipped headlights or DRL on (clause 19.5 of the Russian Road Traffic Rules). Example for Germany: modifications that endanger other road users invalidate the vehicle's operating permit (§ 19(2) StVZO).
- If a change makes operating the vehicle unlawful, restore the original value before driving.
- The manufacturer or dealer may refuse warranty repair of related defects. During servicing, the dealer may overwrite your changes.
8. If something goes wrong
- Do not switch off the ignition abruptly or disconnect the adapter. Wait for the app's message.
- Check the power supply. If the voltage drops, connect a charger.
- Check the connection and read the control unit again.
- Roll the change back in the "History" section.
- If the control unit does not respond or the rollback failed, do not try to write again. Save the logs ("Help → Show data folder in Finder"), contact a specialist or dealer, and write to support: thebordev@gmail.com.
- Do not drive while warnings for the brakes, steering, airbags or engine are lit until the cause has been fixed.