So Its been raining heavily where I live for about 3 days straight. And I don't normally drive my LR but decided to go out and start it.

Well I turn the key to the start position and I hear a relay clicking very rapidly from what sounds like behind the glovebox. Turn the key to start it and nothing happens.

Does anyone know what this could be?

 

I have had this happen to me a few times when I have been playing in deepish puddles or other situations where I would likely get water pretty high into the engine compartment. I don't know what causes this for sure, but it would always work again after I waited a while for things to "dry out".

 

Sounds like your ECU is possibly full of water.
Unhook the battery, on the passenger fender is a black box, take it out, open it up and see how much water is in there.
Dry it out, seal it with silicone caulk, let it dry and put it back.

 

Mine did this for a while. Every time it would rain. It would usually dry out in a few days and start working but I wanted to permenantly fix this. It was the Alarm box. WHat year is yours? I the Alarm light below the radio constantly lit? When its lit the car wont start. I searched on the web for a while an found a way to disable the "no start" function of the box and have not had any problems since. Also I found my Leak.

 

So share this tip with the rest of us please.

 

Its Different for your truck because of the year. But for the 95 and earlier you just crimp the two Orange/Black wires going into the alarm box together with a wire splicer. Do some googleing on " 97 discovery alarm box bypass" or similar and you will find a few wright ups.