Take off the plastic cover (clipped in, it comes out easy).
Look under there for 2 round things suspended by metal clips before (in front off) the radiator. Those unbolt and come out-> those are the horns.
You can see theme behind the grill in this pict:
One is vertical on the left (from POV of picture itself), the other is on right at the top and horizontal. Both are right at the the middle grill bars-> the round things.