There is either a burnt out fuse, or a problem with your brake light switch, located under the dash connected to brake peddle arm.
Fuse
my back brake lights don't work, but the brake light on the back door does what could be wrong
whats wrong with them??
=I don't know about the brake lights. I know that most cars, when you turn it off and get out, the head lights and main backlights stays on for a while but then goes off. The brake lights? Maybe it's the way that car is or something is wrong with the brake or you have it on wrong.=
Maybe it is not connected properly or you bought the wrong type of bulb.
wrong bulbs or bad earth
Check the brake switch at the pedal.
If the gearshift pops out of gear it is probably due to worn shifter detents.
Blown fuse
It is important to pay attention to the warning lights on the dashboard. When the ABS and brake lights flask that means there is something wrong with the brake system.
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And 'appen the brake lights come on when you switch on the side lights? Someone has swopped the wiring over... or forced the bulbs into the sockets the wrong way 'round!