Tech tips Brake Bleeding Tips For Dual Brake Systems Ok folks, there has been much head scratching about this procedure in the past. Look no further. The factory shop manuals only indicates to bleed brakes to get the "brake" warning light to stop being on. Ok, here's the trick: You need to cross bleed the system with an ASSISTANT (very important) have the assistant sit in the car and slowly press the brake pedal to the floor. Open the bleeder screw and let drain completely, close the bleeder screw and repeat until air is out of system. Then move to the rear/front opposite wheel and do the same. Repeat this until the assistant says the light is no longer lit. Inside the proportioning valve is a pin which moves back and forth with this bleeding action. If it is not done properly you will not get the brake light to extinguish and the brake system will have uneven pressure. This WILL cause dangerous braking and random braking power since the pin is in different locations blocking either front or rear brake lines. Hope this helps explain how this system works. If you have any further questions please email or phone us.