what about car manufacturers that decide not to put them into their cars?
they cant be shut down, most of them are foreign and they cant shut down a
car manufacturer n the UK, think of the job losses and tax losses

WTF are you on about? That is the stupidest thing I have ever heard.
However, given your unsucessful atempts to produce sentences in English,
your comment does not come as a complete surprise.

Are you seriously suggesting that if a car manufacturer decides to produce
a car that does not confirm to UK legal standards (e.g. they decide that
the indicators do not look good on their new car, so they don't bother
putting
them on) that the government will be unable to stop these cars from being
used legally? The government sets legal standards for motor vehicles. If
manufacturers do not produce vehicles that abide by those standards,
then they cannot be used on the public highway, simple as that.

Matt