Horn OK Please
The purpose of the phrase is to alert a driver of a vehicle approaching from behind to sound his/her horn in case they wish to overtake.
The origin of this phrase is unknown. Also, there is no official significance with respect to Indian traffic regulations. No rules in India mandate or suggest the use of such a "slogan" on a vehicle. Still many vehicles are decorated with the phrase Horn OK please.
In Pakistan too, instructions are used in a similar manner, but with rather different styles and phrases. Like the phrase Horn de kar paas karein written in Urdu, often found behind heavy vehicles, trucks, and trailers traveling on long routes or highways.
- Marketplace: India's Cheap Car Stirring Up Noise Radio report on "horn not OK" campaign in India