Dashboard light switch function

Hello everyone....

Just joined after collecting an 05 Discovery to cope with the roads I now drive on in and around Wexford......

So far so good...apart from this switch, which the manual says relates to fog lights...but I switch these on from the main switch (pull out once or twice)

Been round checking all lights with this on and off...so guessing it may have been for some auxilliary lights that have been removed??

Any advice appreciated.....

Thanks,

Adam