Cal. Civil Code
1360(a)(2) provides that an owner may make modifications to the common areas of a "condominium project," "as necessary to facilitate access for persons who are blind, visually handicapped, deaf, or physically disabled, or to alter conditions which could be hazardous to these persons."
This law has never been tested for "equal protection" under the Fair Housing Act, or California Fair Employment and Housing Act. Consequently, it's not certain that you would be able to enforce the law as part of a homeowners association that is not a condominium project.
However, given the manner in which courts generally treat fair housing issues, I don't believe that the HOA would stand a "snowball's chance" of prevailing against you in court, were you to make the modifications -- as long as your modifications are reasonable and within the architectural standards of the community.
You can file a complaint with the California Department of Fair Employment and Housing (DFEH), and let the agency investigate. I believe that this is probably a "slam dunk" in your favor.
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