Hi guys, sorry it may be a silly question but does the battery have to be disconnected before you jump the switch?

Range Rover Sport 2008

Thank you in advance
Rossii

No it doesn't. 
Hung like Einstein, smart as a horse.

I have just managed to fix the same problem.
I removed the RH headlamp which gives good access to the sensor housing and plug.
Removed the housing by pushing in the two clips that are radiator side of the housing and slid it down. They are a bit stiff but persist.
I could then get my (fat) fingers in to unclip the plug.
I found a big fat and bright green insect inside the switch housing which I assume was preventing the microswitch being pushed.
I washed the whole thing, getting rid of all the build up of oil and grit and then replaced it.
Works well, I hope it's not too late.

Well, I got a new switch and looking at the state of the old one, it's not hard to see why the alarm was triggering...
With all that crud on the spring, the metal couldn't have had a good electrical contact...


 "We're in danger, we've got to get out."
"What are you talking about?"
"I've been called a ponce."

I ordered the new-style latch with integrated bonnet (hood) alarm sensor/switch and replaced it myself using information from this forum. I actually went in from the right headlight hole... kind of like doing a laproscopy!
The hood still closes solidly. Time will tell whether I've fixed the annoying False Alarm problem. Thanks everyone!