2013 Land Rover Defender 90 alarming

Hi all,

I have a question regarding my Defender 90 - I can unlock and lock using the key fob, but when locked with the fob, the alarm starts to go off 3-5 mins later. If locked with the key, the alarm does not go off.
When unlocked with the key, the red light on the dash comes on (and stays on). If unlocked with the fob, the red light doesn’t come on.
I have just put a new battery in both fobs and resynchronised them to the vehicle (I think), but this hasn’t changed anything.

Any advice would be great!

Thanks

Does locking with the key actually set the alarm? My TD5 doesn't.
Bonnet sensor can play up a bit.

Locking with the key does not set the alarm. Locking with the fob sets the alarm. Checking the bonnet sensor as Anaconda suggests is a good starting point. A diagnostics check should however pinpoint the fault.

THe only time my alarm has gone off spuriously it was the bonnet alarm swith on the bulkhead that needed straightening up, bonnet was not pushing it down far enough, my neighbour had the same problem on his Range Rover. The bracket may need pushing up a bit as well.