In this case, it is recommended to "retrain" the second remaining working key so that the lost key cannot be used to steal the car.
Then you can buy a second key and "retrain" the system again with two keys. "Retrain" in the order described in the subsection "Procedure for "training" the immobilizer". The only difference is that when you turn on the ignition at the beginning of the procedure, the system status indicator starts to flash at a frequency of 2 times per second.
2. Loss of the "training" red key.
In this case, it is impossible to carry out the procedure of "training" new keys. This means that you can continue to operate the car with the existing working keys, but in case of their loss or malfunction of the immobilizer control unit, you will have to replace both the APS control unit and the engine control controller with new, "untrained" ones. With such a replacement, you can take a new training key and carry out the procedure of "training" the anti-theft system with a working code key.
Warning: Due to the importance of the "training" key, it is recommended to keep it at home in a safe place.
3. Replacing a faulty anti-theft system control unit (immobilizer).
After replacing a faulty immobilizer with a new one, it is necessary to carry out the system "training" procedure described in the subsection "The procedure for "training" the immobilizer". In this case, use the existing training key from the faulty immobilizer. However, there is a difference in paragraph 1 of the "training" section, which is that after turning on the ignition, the LED blinks at a frequency of 1 time per second.
4. Replacing the faulty controller.
A faulty controller can be replaced with a new one ("clean"). It will allow the engine to start regardless of the immobilizer. To activate the anti-theft function, you must perform the procedure described in paragraph 1 ("Lost working black key"), using the available "training" and working keys.
5. The engine does not start.
If, after disarming the anti-theft system, the LED of the system status indicator flashes 1 or 5 times per second when starting the engine, and the engine does not start, this means that the anti-theft system is faulty or there is no connection between the immobilizer unit and the engine management system controller.
If, when starting the engine, the LED flashes 1–2 times and goes out, but the engine still does not start, then the malfunction is not related to the anti-theft system.
6. Control of the interior light switch-off delay.
This function allows you to keep the interior lighting for some time after the car door is closed, which makes it easier for the driver to operate in the dark. For this function to work, the ceiling light switch must be switched to the off position. In this position, when the driver's door is opened, the ceiling light lights up and remains lit for as long as the driver's door is open.
If the vehicle ignition is not turned on, then after closing the driver's door, the lamp remains on for another 12 seconds, after which it smoothly goes out within 4 seconds.
If the door is closed with the car ignition on, the lamp turns off immediately after the door is closed.
[The text is copied from the online resource: VazBook.ru]
If the ignition key is turned to the "on" position while the ceiling light switch-off delay is operating, the ceiling light goes out without delay.
If the door is opened again while the lamp switch-off delay is in effect, the lamp switches on and remains lit for as long as the door is open.