Does it do anything other than turn a light on in the tach?

 

THAT Fog Light Switch activates the TAIL Fog Lights. Do you have a 2006-2010, or a 2010-2015? The earlier models without LED tail lights have ONE Tail Fog Light while the later cars with LEDs have two.

 

Of course! I should have thought to look at the tail lights, especially since our 2011 Range Rover has two fog light switches, one for the front bumper fogs and one for the tail lights. The XKR-S is a 2013, I just drove it in the dark for the first time tonight. The low beam cutoff is quite low, high beams are excellent.

 

You can adjust the aiming point for the low beams. I couldn't see anything when I first replaced my failing blue showing HID's. There's a black cover on the top back and housing. Pop it out and a 5 or 6mm Allen will allow adjustment. Bumped mine up until the lamps just barely light up a stop sign at 100 yards and it made a huge improvement without annoying oncoming traffic. Before 50 yards out was dark. Before new HID's, 25 yards out was dark and the fog lights were brighter.