2 minutes ago, Davemk said:

 

The drivers door doesn't deadlock because you can manually unlock it with the key. The doors deadlock when the battery is totally dead, so will not happen while you are in it. 

 

When the battery is totally flat, the remote part of the key is totally useless. That's exactly why they put a physical key as part of the fob so you can at least get into the vehicle. 

 

I've known all that for many years, but the key lock does deadlock the driver's  door lock as does the remote central locking function. The only time that these cars can not be deadlocked is when the battery is dead before the car is locked up, or the battery removed  before the car is locked up.

I have a plug in voltmeter in my cars power socket, very cheap to buy, also as the batterys voltage drops certain items

cease working turned off by the car computer.