2002 Chevrolet S-10

Brakes problem
2002 Chevy S-10 6 cyl Four Wheel Drive Automatic 101700 miles

I changed my brake pads tonight and when I depressed the cylinder to allow the new pads to fit over the rotor I forced brake fluid from the reservoir. I have anti-lock brakes and think that when I forced that fluid out I messed the system up because now I can push the pedal to the floor every time I use the brakes. I have braking ability but it's not what I know it should be. Can you tell me how to reset the anti-lock brake system?
November 2, 2008.

Did you bleed the hydraulic control unit (HCU) to see if this helps?

No I didn't. Where is that and how do I go about doing so?

Nov 3, 2008.
I noticed that you never mentioned anything about bleeding your brakes after changing them. This is always necessary so here are the instructions for your vehicle.

Raise the vehicle in order to access the system bleed screws. Bleed the system at the right rear wheel first.

Install a clear hose on the bleed screw. Immerse the opposite end of the hose into a container partially filled with clean DOT 3 brake fluid. Open the bleed screw 1/2 to 1 full turn.

Have a helper slowly depress the brake pedal. While the pedal is depressed to its full extent, tighten the bleed screw. Release the brake pedal and wait 10-15 seconds for the master cylinder pistons to return to the home position.

Repeat the previous steps for the remaining wheels. The brake fluid which is present at each bleed screw should be clean and free of air. This procedure may use more than a pint of fluid per wheel. Check the master cylinder fluid level every four to six strokes of the brake pedal in order to avoid running the system dry.
Bleed all four wheels again using the same steps to remove the remaining air from the brake system. You can bleed the system as many times as necessary in order to obtain the appropriate feel of the pedal.