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This symbol means that one or more of the brake lights or taillights are not working correctly. When you start the vehicle and press the brake pedal if the light comes on instantly this is a brake light bulb problem. If you start the vehicle without your foot on the brake then turn the headlights on and the symbol illuminates this means one of you're taillight bulbs are not illuminating. Check all the bulbs let me know what you find. there have been problems with the taillight failure relay also but we can get into that once we determine whether not the bulbs are bad.Skyvisions