Section 26521.

Cal. Vehicle Code - VEH § 26521.
in effect
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Motor vehicles required to be equipped with power brakes and equipped with vacuum or vacuum-assisted brakes and motor vehicles used to tow vehicles equipped with vacuum brakes or vacuum-assisted brakes shall be equipped with either an audible or visible warning signal to indicate readily to the driver when the vacuum drops to eight inches of mercury and less. A vacuum gauge shall not be deemed to meet this requirement. This section shall not apply to a two-axle motor truck operated singly nor to any motor vehicle manufactured prior to 1964.
Source: CA Legislative Counsel Bulk DataURL: https://downloads.leginfo.legislature.ca.gov/pubinfo_2025.zipFetched: 6/27/2026

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