@zaarsalik1 has a very valid point.
One horn could be of the security beep. But in Yaris horn is separate single horn and separate beep beep for security.
Just like fortuner has a separate beep beep and 2 horns similar to corolla setup.
Kheir I ordered these from lahore for rs. 2000 took off from a half cut Civic.
Will take these along on first service. Will let honda guys put them on. They should be grip to grip.
Will also try to go through the owners manual today and see the horns setup
Will also stand in front of the car let someone press horns to check which one is the culprit