Alarm/immobiliser problem

[Grumpy]

I locked the Disco (200tdi) in the normal way with the remote last Sunday tried to open it again today with the remote and it did not open there was no flashing alarm light on the dash, assumed a flat battery, so I opened the car with the key.
Tried to start it and nothing happened, the ignition lights did not dim but the clock and the radio dimmed, put on the lights they did not dim so no heavy load at the starter motor, battery reads 11.87V
I'm assumming now the immobiliser is faulty, can anybody shed any light on the problem, where is the immoiliser box? are there any fuses I should be checking? any info gratefully recieved

[gtomo2]

pop your bonnet and have a look at the wiring loom on the passenger side you will see some cloth wrapped around the wiring loom.Cut the cloth back and you will see three wires these are fuseable link wires and they get water in and brack off. either resolder them or replace them with normal fuses.

[hobbit]

Try running a battery booster cable from the neg on the battery to the engine directly