Where is the headlight sensor locted on a LR Disco 3

Go to online owners websites for tips as LR have massive electrical glitches.

Hi welcome main problems are the abs valves causing the 3 dash lights (search 3 amigos online) a really badly sited compressor can cause air suspension models to fail giving the bags a slow leak the V8 is a solid engine but can have radiator expansion tank and cap failures
the other issue is electrics windows and door looms are problematic

Check that your fuses and bulbs are still fine

Only the rear suspension on the Disco 2 was air. The Disco 3 SE & HSE had air front and back.

These vehicles are very sensitive to having the exact make when it comes to parts. Many of the aftermarket parts will only create more problems and probably not work. I would certainly get a sensor from the dealership. I have never seen another make of cars be so specific to having the correct parts.

Check fuses.

Air intake temperature sensor is fitted in the hose from the air cleaner box to the intake manifold. You will see a unit with electrical connection .
Hope this helps

Change your battery terminals.

http://carservicemanuals.blogspot.com/2008/06/download-land-rover-discovery-workshop.html

Just had this same issue with my 57 plate Discovery SE - great guy from the AA took the small plate off that sits immediately to the rear of the hanbrake button in the central console - he then hooked a wire around the cable you see in there and gave it a mighty tug. The result is that my brake is now disengaged (rather than stuck-on as before) and LR will need to cure the source of the problem under warranty. Car is automatic so can use "park" until full repair.

9 times out of 10 it is the ABS modulator for the disco II's. That being said, i hope you're sitting down...only a LR shop or a shop with auto logic can fix it and it's gonna cost you... A new modulator costs around 2k. if you can get the dealer to install a remanufactured one, it will cost you around 700 for the part and about 3-4 hours of labor.