I dont have remot for alarm 2003 land rover discover

Has the battery ever been replaced? It may only need a new battery. When the battery has been replaced it will need to be 'synched' to the central locking. A few links to help you -
Key fob not working

How To Replace Land Rover Freelander Key Fob Battery 2002 2003 2004 2005

Engine immobiliser must be disabled by a Rover TedtBook. Most likely only your local dealer will be so equipped. There are ways to work around or through thus common isssue. Be sure youve done the following before dropping the bucks at the dealer:
Replace batteries in your remote
Resync remote (instructions in your owners manual)
Try resetting the alarm ECM by disconnecting negative battery cable, turn ignition to second position, leave drivers door open, then reattach your negative lead, shut the hood, get in the drivers seat, turn off the ignition then attempt starting. Hoid and drivers door must be shut when you attempt to turn it over.
Last but not least therd is the EKA procedure. Step by step instructiona available on this and many other sites. Google "EKA procedure" adding your model and year in the search box.
Good luck. Feel free to message me directly if you are unable to find the instructions.

Easiest way is to find the manual on line, if you do not already have it, and pull the fuse for the alarm. That should disable it. Then next dealer visit you can have it reset and you'll be good to go.

your remote is picking up another signal some place and your cars being haunted by it
reset alarm settings
now the other problem is your battery is getting weak loosing its charge because its constantly on simple get charger to trickel charge system or replace battery

Check the batery in your remote

change the remote batery most car dealers shouled be moure than happay to do this

The alarm and the central locking are all part of the remote keying system. You will not fix it with changing fuses because it is likely the ECU needs to be be reset. Unfortunately, it will require a visit to an authorised workshop to do this

Try and use this information to reprogram your remotes. Click on the download above the information. Hope this helps... http://www.autozmagz.com/search/land+rover+freelander+remote+entry+programming

Unfortunately, there is a trick to replacing the battery.
1) Open the Driver side door.
2) Open the Bonnet and take the battery cover off.
3) Use your remote to lock and unlock the car (keeping the driver side door open)
4) Pull the Negative Lead from the battery first, followed by the Positive Lead.
5) Change or replace with charged battery.
6) Closed down Bonnet.
7) Your windows, sunroof, and key FOB will not work... so follow the next steps.

7a) Insert your key, with door closed into the exterior lock on driver's side.
7b) While turning the key to lock the door, hold down the "lock" button on your remote for 5 seconds while in "lick" position
7c) Your remote will reset, and you should be able to use your remote now
7d) While driving, roll each window down twice. On your third attempt, you should only have to touch the window button, and the window will have reset

Enjoy your Rover!
MIke

You must enter the system using the EKA code, it will written in the service book how to activate the EKA. If you dont have the EKA code, you will have to take the car to the dealer to reset the system and give you the code. hope that helps