How to Replace the Abs Control Module on a 1995 S10

The Chevy S10 is a lot of things to a lot of people, but it is, above all else, still a truck. And a truck, by definition, is light in the rear to allow for its cargo carrying and towing capabilities. This is great when you're actually setting the truck to such a task, but not so much when it comes to unloaded driving and braking performance. Trucks like the S10 were some of the first vehicles mass-produced with standard antilock brakes, primarily to keep the rear under control during panic stops. Replacing the S10's ABS control module is more dirty than difficult, and is certainly within the reach of most weekend mechanics.

Instructions

1

Locate the ABS control module under the hood. Follow the lines from your brake master cylinder the the modulator; you'll find it near the washer tank on the driver-side wheel well. Neither the mechanical, nor the electrical parts of the modulator control units are serviceable, so any kind of failure means replacing the whole thing as a unit. Remove two washer tank bolts, using a socket and a ratchet, then set the washer tank off to the side to access the modulator.

2

Unplug all three of the module's electrical connectors. You might consider wrapping the electrical connectors and covering their terminals with duct tape to keep brake fluid off of them during installation. Brake fluid is death for anything electrical, so consider keeping the two separate your top priority.

3

Disconnect the brake lines where they connect to the modulator, using a line wrench. Wrap an old rag around the fittings as you loosen them to absorb spilled fluid, then tape the ends of the lines to reduce drips and line contamination while you're working. If the first fitting gives you a fight, spray all of them with some penetrating oil and let it soak in for ten minutes.

4

Remove the upper and lower bracket bolts from the chassis and the modulator, using a ratchet. You'll find two horizontal upper bracket bolts, three vertical lower bolts and two vertical bracket-to-modulator bolts in the middle of the bracket. Once you have them out, pull the modulator free.

5

Make sure that the brake line threads on your new modulator are clean and free of grease or oil, then mount the new modulator in place of the old one. Install the bracket and torque the bracket-to-chassis bolts to 20 foot-pounds, using a torque wrench. Torque the bracket-to-module bolts to 5 foot-pounds. Install the brake lines and tighten them to 16 foot pounds.

6

Bleed the brake system as you would with any other vehicle -- with one exception. You'll find four bleed screws on the module. The top two must remain closed when the unit is not pressurized and the two internal bleeders on either side must be opened one-quarter to one-half turn counter-clockwise before you begin the bleed process. The left-hand valve is for the rear brakes and the right-hand valve is for the front brakes.

7

Pressurize the system, either with the brake pedal or with a pressure bleeder, and close the module bleeder valves as you lift off the pedal or release pressure. Open one of the valves again before you press the brake pedal, and close it when you reach the bottom of the pedal stroke. Add brake fluid and repeat with the first valve, followed by the opposite valve, until the fluid comes out clear and free of bubbles. Proceed to bleed the entire brake system at the calipers to get rid of air trapped in the lines.