City law outlines appropriate times for drivers to honk horn
May 23, 2017 | 77° | Check Traffic

Hawaii News| Kokua Line

City law outlines appropriate times for drivers to honk horn


Question: One afternoon, a guy almost hit my car when he veered into my lane. I sounded my horn to let him know I was next to him. He stopped at the next red light to confront me. The gist of what he said was that I was uncool for honking and that he already knew he was about to hit me, so next time don’t honk. I was under the impression that the horn was installed on vehicles to warn other drivers and pedestrians and avert an accident. Is there any driver’s etiquette regarding when and how to use the horn?

Answer: It’s not just driver’s etiquette, but a law that spells out when you should — and should not — honk your horn.

The law allows a driver to toot the horn to warn someone when it’s “reasonably necessary” for safety, said Capt. Andrew Lum, spokesman for the Honolulu Police Department.

For example, when a collision appears imminent, “the use of the horn is lawful to give an audible warning.”

When to use it can seem subjective, depending on which driver you ask, Lum acknowledged, “but the law clearly allows for the use of a horn to give an audible warning when it is reasonably necessary to ensure safe operation.”

However, the law prohibits using a horn in any other situation, such as a greeting or honking at someone who doesn’t react quickly to a green light, he said.

Section 15-19.27 of the Revised Ordinances of Honolulu specifically says, “The driver of a motor vehicle shall, when reasonably necessary to ensure safe operation, give audible warning with his or her horn; but shall not otherwise use such horn when upon a highway.”

It also says every vehicle has to have a horn in “good working order and capable of emitting sound audible under normal conditions from a distance of not less than 200 feet,” but not emit “an unreasonably loud or harsh sound or a whistle.”

Question: We are shipping our car to California for our daughter, who will be a college senior. California law allows an out-of-state car driven by a nonresident student 23 years or younger to remain registered in their home state. California law also does not require safety checks, only emission inspections. Our local insurer said we can continue to include her on our Hawaii-based policy as long as she is a dependent. If the car is physically in California but registered and insured in Hawaii, would the city accept a California-type safety inspection?

Answer: The Honolulu Motor Vehicles & Licensing Division does not accept out-of-state safety inspections, but that shouldn’t be a problem in your case.

 If a Hawaii-registered vehicle is outside the state and the applicant is a resident of Hawaii, the Hawaii registration can be renewed and a safety inspection would not be required, said Dennis Kamimura, administrator of the Motor Vehicles & Licensing Division.

However, the registration renewal must be accompanied by a completed CS-L-64 resident form — see

Applicants are advised to check with whatever state the vehicle is in to make sure a Hawaii registration can be maintained.

If you have further registration questions, call 532-4325.


To Honolulu police officers Ah You, Shiraishi and others for assisting me in Manoa on May 6 when I locked my car with the key still in the ignition. The officers resolved my dilemma with exemplary efficiency, courtesy and professionalism and without any expectation of acknowledgement, as evidenced by their prompt departure to another call before I could even get their full names!

— Grateful


Write to “Kokua Line” at Honolulu Star-Advertiser, 7 Waterfront Plaza, Suite 210, 500 Ala Moana Blvd., Honolulu 96813; call 529-4773; fax 529-4750; or email

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