Hello, hive! I have a 1999 GMC K1500 Suburban. When I step on the brake pedal, no keys in switch, the dash and marker lights come on. When headlights are off, driving normally, both turn signals work normally, but the dash and marker lights flash with right turn signal. When headlights are on, left signaL works normally, but right signal buzzes a little at the relay, but does not blink, even though the rear lamp does light on the right side. I am at a loss. So is my mechanic. Help??