microcontroller 604 which senses input from the operator brake pedal switch 606 and the accelerometer fig5 608 the control of power to the flasher array to effect the desired flashing is caused by the pulse width modulator 610 a failsafe relay 612 can be switched from the normally closed to normally open position when the microcontroller 604 determines that flashing is appropriate if the microcontroller 604 is in a lockout time period to preclude flashing and the hard braking is sensed by the accelerometer 608 the microcontroller 604 would override the lockout time period to further effect flashing by the switching of relay 612 voltage regulator 614 drops down a typical vehicle supply voltage of 12 volts to the appropriate operating voltage for devices in the circuit while electronic relays 616 618 convert the control signals from the microcontroller 604 and pulse width modulator 610 into the appropriate operating voltages for the relay 612 and the lamp array 602 it is within the scope of the invention to alternatively program the microcontroller so it can effect the flashing of the lamp array 602 upon receiving a sudden increased vehicle deceleration or acceleration sensed by accelerometer 608 even without the closing of the brake pedal switch 606 such a situation can occur when the vehicle contacts some driving force or encouraged some dangerous situation in which flashing would be desired for example if the accelerometer sensed a movement greater than 0 5 g with reference to fig7 a and 7b a back up collision avoidance device is shown it is intended to be remotely controlled by a vehicle operator.