My Range Rover fob won't activate the locking system and now the car has immobilised - what do I do?

The key fob for my Range Rover P38 will not activate the central locking and the car will not start, it has been immobilised. I am not covered by any insurance policy or breakdown cover through RAC as I have already checked. Numerous local auto specialists do not seem to be able to assist and one auto lock specialist said this particular problem is very difficult to solve as it involves all the electrical circuits situated under the driver seat. Can you assist in any way please?
Usually when the battery in a keyfob fails, the fob loses its code, but there is just a chance there is enough left in the battery for the fob to retain its code. Go to a branch of Timpsons, get them to replace the battery, then see if that works. (The battery has to be replaced within 10 seconds or the fob loses the code completely, so have the replacement battery out of its pack and ready.) If that fails, then you're in the hands of specialists or a dealer. If it works, get yourself a spare key and fob made.
Answered by Honest John on

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