Discovery 2 alarm beep and interior lights staying on

3am the other morning myself and neighbours woken up by my Discovery 2 Alarm going off, ran down stairs with baseball bat in hand and out into the yard to find alarm going off and interior lights on but doors all locked.

pressed open button on key fob and alarm went off. opened and closed doors and pressed lock button on key fob, one beep and interior lights stayed on.

had to resort to removing middle bulb and switching front and rear courtesy lights to off position and leaving the car unlocked for the fear of the alarm going off again.

symptoms now are, interior lights stay on even when engine running and driving also when activating door locking and alarm, also alarm makes single beep when locking doors from either fob or key in door.

only way i can leave the car semi secure is to turn off interior lights and press the lock button on key fob, this locks doors and i still get a single beep. also light around ignition key stays illuminated for quite sometime but is off next day when i go to it. At this point the key fob wont unlock the doors and have to unlock it with key which sets the alarm going until i disarm it by turning ignition on.

have tried disconnecting battery for a while, no change on reconnection.
have tried shorting bonnet switch, have tested bonnet switch,
passenger front door was not unlocking or locking so bought a new latch and fitted it hoping it might be the problem, no change, have checked connections to all latches by removing all door cards, all look dry clean and good.

am at my wits end and given up now, can anyone please shed some light on my problem, one problem after another and probably the worst car i have ever had the pleasure of owning.

Many thanks

Paddy

sounds like either the nsf door solenoid failed or one of the door switches failed making the alarm think that a door or the bonnet is open. find if the nsf solenoid/motor is getting a feed to lock/unlock.

yes i was having a problem with the nsf door but i have changed the whole latch for a new unit and it works now but i still have the problem, have removed drivers door latch too and it seems to be working ok. can i check anywhere with a multi meter to check if all switches are working correctly without stripping the doors apart again?

Also it was a cold damp night when it first failed and has been damp and cold since, will this have any impact on the problem?

i had the opposite problem with interior light. wouldnt come on. traced it to multi pin plug behind kick panel in passenger footwell. purple wire. water gets in and causes corrosion/shorts etc.
have you got sun roofs? they probably leak and can cause problems with wiring within roof lining. i think the alarm fob sensor is up there, so vunerable. used to get water running out of the front interior light after showers. sun roof sealed so ok now.

have a look at the fusebox under steering wheel remove and check for water damage
also have a look round the bcu for any water ingress