Alarm - remote control key not working

If the alarm cannot be deactivated with the remote control key, e.g. if the key's battery is discharged - the car can be unlocked, disarmed and the engine started as follows:
Open the driver's door with the detachable key blade.
The alarm is triggered, the alarm indicator flashes rapidly and the siren sounds.
P3-V60H Fjärrnyckel + Start/Stop-knapp
Insert the remote control key in the ignition switch.
The alarm is deactivated and the alarm indicator goes out.
Start the engine.