Hi there,
I have had the same problem with My disco x plate 2000, alarm going to sleep over night exactly as you describe.
The remedy I have found to the problem is a Technical bullet in on the rave CD. This was backed up by Land rover.
the reciever in the roof by the rear sunroof mechanism, on the left hand side of the vehicle, can become lazy and go to sleep, to remedy this you need to replace it, about £40 quid from landrover, I have just replaced mine this afternoon, and i am looking forward with interest tomorrow morning to see if this solves the problem....lets hope so!!!
I will quote from rave below for you.....
[FONT=Arial,Italic]PROBLEM:
[/FONT][FONT=Arial,Bold]REMOTE HANDSET FAILS TO UNLOCK VEHICLE - ALARM RECEIVER
After the vehicle has stood for an extended period (e.g. overnight), the remote handset will not unlock the vehicle. Unlocking using the key restores normal operation.
[/FONT][FONT=Arial,Italic]CAUSE:
[/FONT][FONT=Arial,Bold]There are a number of possible causes:
1. Remote handsets not in synchronization with the Body Control Unit (BCU).
2. Poor earth connection on the alarm receiver.
3. Lack of continuity between the alarm receiver and the BCU, possibly due to a trapped or chafed harness in the A post area.
4. The alarm receiver has detected interference over an extended period, resulting in the BCU going into sleep mode.
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ACTION:
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Interrogate the alarm system using TestBook, noting the following points:
[/FONT][FONT=Arial,Italic]CAUSE 1 [/FONT][FONT=Arial,Bold]- Refer to Technical Bulletin 0021 - Handset Diagnosis.
[/FONT][FONT=Arial,Italic]CAUSE 2 [/FONT][FONT=Arial,Bold]- Ensure that the alarm receiver earth is clean and securely tightened to 7 Nm.
[/FONT][FONT=Arial,Italic]CAUSE 3 [/FONT][FONT=Arial,Bold]- Check wiring continuity between the alarm receiver and the BCU.
[/FONT][FONT=Arial,Italic]CAUSE 4 [/FONT][FONT=Arial,Bold]- Replace the alarm receiver with the appropriate revised receiver
detailed in [/FONT][FONT=Arial,Italic][FONT=Arial,Italic]PARTS INFORMATION [/FONT][/FONT][FONT=Arial,Bold]using the following new procedure.[/FONT]
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[FONT=Arial,Bold]Hope that helps.....It is a bit of a fiddle and a sod to get to but doable. LAnd Rover get 6 mins to change.......... for a warranty claim!!!! HA HA!![/FONT]
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[FONT=Arial,Bold]Good Luck, will let you know if mine is working correctly tomorrow??
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