central locking problem.

was just starting to feel good about my disco. Got most jobs sorted when, 3 days ago, it wouldn't lock on the fob. It gives the false lock beep and nothing else. The bonnet connector was disconnected in November when I bought the vehicle cos this sometimes gave the same false locking. Yesterday, however, the locking worked fine and I just put it down "one of them disco things" but it has done it all day today. I have a battery monitor plugged into the cigarette lighter and I did notice though that when I switch the ignition off the monitor was still juiced up for a little while which I don't remember from before this problem. I have now unplugged suspecting that might be the cause. but it wasn't. So to lock up I now have to lock the doors from the switch inside, get out and lock the drivers door with the key. This isn't a great hardship but as I work shifts and park up at odd hours the false locking beep will no doubt annoy my neighbours. Any advice most welcome. Is it really true what a disco owner mate says that all discos are cursed with having 3 problems and when you fix one another appears.

driver's door switch or it's circuit to the BCU... to make sure, leave the windows open, lock the car with the key then open the doors one by one...start with the driver's door as 99% that's the problem... if the alarm will not go off it means that there's the problem as the BCU doesnt get the earth from that door for some reason(the most common is the switch but can de interrupted wiring or bad contact at the BCU if there's water ingress in the area(common aswell)...if tyhe alarm goes off unlock with fob to shut it down, lock back and go to other door...and so on untill you find the faulty door... watch carefully my replies here http://www.landyzone.co.uk/lz/f8/discovery-2-t-reg-locking-issue-247991.html

following on.... Just tried plugging the battery monitor in again with disco not running and its showing 5volts going to the cigarette socket. goes up to a nice 14volts when started. no flashing LED for alarm active when locked so im assuming that something is keeping my disco awake and stopping the alarm from setting.
Any thoughts still most welcome.

that 5V reading might not be relevant... it could be some residual/inductive voltage... did i misunderstand or mix your post with the other, just confirm do the fob work for unlock? ...as long as you get the misslock warning it means the alarm is partially armed and the receiver+BCU are getting the signal from the fob...lock with fob to hear the misslock then open the driver's door(regardless of the doors are mechanically locked or not)...if nothing happens start opening other doors...tell me if the alarm goes off or not at a moment

The fob works with unlocking and tries to lock but gets the misslock beep and the doors stay unlocked. The reason I mentioned the battery meter is cos before this problem when I switched ignition off and removed the key the meter shut down to just showing the time. Now it stays juiced up and shows 5v and has a back light lit. seems a strange coincidence not to be related. might just be caused by not cause of the problem. ill try the doors tomorrow as its dark now and neighbours wouldn't appreciate the horn beeping as I keep trying.

Update. I have tried the fob and still get the misslock beep from the horn. No flashing LED for alarm and when I open the doors I don't get the alarm going off. I tried reconnecting the bonnet switch, mainly through desperation, but it made no difference. If I sit in car and lock all doors on the button then try the fob I still get the misslock beep. I have not driven the landy since this started and thankfully nothing seems to be draining the battery. There is a local garage a couple of miles from me who specialises in landy's so may have to pay him a visit as i have no ideas other than ripping the door panels off. Im reluctant to do this though as it feels more to do with the cigarette socket staying slightly juiced up as this happened at the same time. On night shifts from 2morrow and then on holiday so will look into it more when i get back. Many thanks for the advice posted here and on other posts ive read.

IMO the driver's door latch is gone or short to earth on the circuit to BCU.... it should at least mechanically activate the central locking...and off course as long as the alarm is not active(flashing LED) it will not go off no matter which door you open

aaahhhaaa... a partial success. having found my landy battery close to death I was forced to put him on charge giving me the incentive to explore this problem a little. fuse F20 (interior lights/radio/clock/remobilise) when removed fixes the problem. when I bought my landy I had a problem with the battery draining that fixed itself when I changed the radio/cassette for an MP3 player. following that I had a problem with the interior lights not working that, with your help, I traced to a corroded wire in passenger footwell. Im guessing that my fix wasn't as good as it should have been and will have another bash in a couple of weeks when I get back off holiday. So to recap. with fuse F20 removed all doors lock/unlock on the fob and the alarm works. my battery monitor plugged in ciggy socket drops out of service when engine is off as it used to. of course, no interior lights/radio/clock but as the landy will be parked up for a couple of weeks this aint a problem atm. Just wish the "parking break fault" on my Jag was as easy to fix
thanks for help and advice offered and will keep you posted if the saga continues past looking for a dodgy wire.

aaaaaaHA... interesting , next job is to unplug the passive remobilisation exciter coil(it's that thing around the ignition barrel-C0049), put back fuse F20 and check then, it's possible that there's a partial short in that coil...if no joy i'll tell you what to do next... just confirm after you lock the alarm LED starts flashing with that fuse removed?

No idea what that is so will dig out my rave when I get back from holiday. Thanks for the pointers.

just tidying up some posts. This problem seemed to almost fix itself after I removed the remobilisation exciter coil and put it back in. there still seems to be something not right but it works ok.