Highland, CA Noise Ordinances: Vehicle Noise (2026)

Section 8.50.040 of the Highland Municipal Code is titled Excessive noise and vibration emanating from a motor vehicle. It bars a person from operating or occupying a motor vehicle on any public right-of-way, public place or private property while using any radio, stereo receiver, musical instrument, television, computer, compact disc player, tape recorder, cassette player or other sound device inside the vehicle so that the sound is plainly audible at a distance of 50 feet from the vehicle. For a vehicle on private property, the line moves to the property line. Both the driver and any occupant operating or permitting the device fall under the rule.

The standard is the plainly audible test in § 8.50.020: sound detectable by a person using unaided hearing, where detecting the vibration from the rhythmic bass component is sufficient. No decibel reading is needed.

Mechanical noise is a separate item in § 8.50.030(A). Sounding a horn or signal device other than as the Vehicle Code or other state laws require or permit is unlawful. So is racing the engine of a vehicle that is not in motion, except when repairing, adjusting or testing it. Operating a vehicle on a public right-of-way, public place or private property in a residential zone is also unlawful when the exhaust muffler, intake muffler or other noise abatement device has been modified so that the noise emitted is increased above what the vehicle produced as originally manufactured.

The remedy for stereo noise is the strongest in the chapter. Section 8.50.040(C)(4) authorizes immediate confiscation and impoundment as evidence of the components producing the noise, or of the motor vehicle itself if the component cannot be removed without harming the vehicle or the component. A person claiming legal ownership of an impounded vehicle in the City of Highland has seven calendar days from the confiscation to file a written return request with the police department, which processes it under its adopted procedures.