E36 Alarm/Central Locking, please help

I have a 97 E36, never had any problems but the alarm has just stopped working for no apparent reason. It is a bmw alarm but am told it is an after
sales one. I have tested the remote and it is giving out a signal but the car is not picking up on it, any suggestions or where to look at all?
also seperate issue but I have now had to resort to using the key to cenral lock the car. Sometimes the locking mechanism does not lock the boot and sometimes it does. It appears to be when the car is on a gradient where the boot is higher that it doesnt lock, this could just be a co-incidence. Any help would be much appreicated. Kind Regards
Toby snipped-for-privacy@Beer.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
1. Close all doors, trunk, and hood. 2. The security system must be in "disarm" mode. The key must be removed from the ignition key slot.
Enter Code-Learning Mode 3. Open the trunk and leave it open. 4. Open the driver's door and sit in the driver's seat. 5. Close the driver's door. 6. Cycle the ignition switch five times between the "off" position and position 2 (ignition "ON", all dash warning lamps will illuminate). The red status LED will illuminate continuously, and the siren will "chirp" once, to indicate that the code-learning mode has been initiated.
DO NOT START THE ENGINE
The ignition switch cycling in step #6 must be performed within ten seconds.
The sequence in steps #1-6 must be performed within 45 seconds.
Registering/Delete ID Code(s) 7. Open driver's door, (remain seated in driver's seat) 8. Close driver's door. 9. Press and release any button on the remote you wish to register into the system. The status LED will shut off momentarily to indicate that one ID code has been registered. 10. Repeat steps 7 through 9 to register the remaining three ID codes.
Exiting Code-Learning Mode 11. Open driver's door, and exit from vehicle, leaving the door opened. 12. Close trunk. 13. Close driver's door. The LED will turn off and the siren will "chirp" twice. 14. The initialization procedure is now completed, test all remotes to confirm operation.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I have Z3 1996 trying to fin out if the remote type is 82 11 1 469 448 can be use to program the alarm unit? How do I reset the alarm unit you know like a master reset to start fresh?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.