The solution for the hybred car problem for the blind is simple, they must
have noise makers. It need not be a steam whistle or 747 jet engine, but
they must be as noisy as the traffic around them. As more and more people
buy them, this sound volume could decrease slowly over the years.
I fear the idea of having them make noise is going to not sit well with either customers nor manufacturers. The additional cost will be negligable, but customer dissatisfaction will be high and most simply will not care enough about our needs to make a difference in the marketplace.
We have no clout in the automobile market as we do not drive and buy few cars, even if for sighted spouses or kids. This may need to be a subject for legislation, as if we did not already have enough laws.