Brake lights are lit whenever the ignition switch is on - and cruse control has stopped working.
Why would brake lights stay on all the time? on 2003 Mercedes-Benz SLK320
The brake light switch is bad or has come out of adjustment. Usually contacts the brake pedal arm.
1 more answer
SOUNDS LIKE BRAKE LIGHT SWITCH IS BAD, THIS SWITCH ACTIVATES CRUSE CONTROL GOOD LUCK