2004 Nissan Micra boot won't open.

[needawin]

My daughter has had a problem with the boot for a while. (It is a remote locking boot only and can not be opened manually).
At times while driving you could hear the boot unlocking itself for no apparent reason. Now the boot has locked permanently and will not open by the remote. If you put your ear to the boot and operate the key fob there is no sound whatsoever from the lock.
Also same car. The passenger airbag light will not go out on the dashboard panel.
Any tips greatly appreciated.

[TWR]

Look at the lock Mechanism when the boot is open, is it slack? it is held in place by Torx Screws.

[needawin]

The boot is locked

[TWR]

Go in through the drivers door, drop the rear seats then release the boot catch.

[needawin]

I can do that I suppose but does anyone have any idea what is causing it to operate by itself?

[TWR]

Either one door has been left part open or the boot or another lock on the body NOT THE DOOR is loose, check them all for tightness.

[chas2008]

Possibly the tailgate central locking motor has failed or seized, the way to check is to put a live feed to it.

[needawin]

Just fixed it for £1. Nissan wanted £40.

[needawin]

Sorry misprint. Nissan wanted £140