How do you bleed Kelsey Hayes anti lock brakes?

Turn the ignition on and start the engine. Press down firmly on the brake pedal several times. If the pedal does not feel firm, turn the engine off, pump the pedal to relieve residual pressure in the system, and bleed each of the four brakes as before to get rid of any air in the system.

When did Kelsey Hayes come out with anti lock brakes?

In 1990, Kelsey-Hayes introduced a new four-wheel anti-lock braking system (EBC4) on General Motors M- and L-series minivans (Chevrolet Astro and GMC Safari). General Motors refers to the system as 4WAL.

What are the brakes on a Kelsey Hayes 4wal?

KELSEY-HAYES 4WAL ELECTRO-HYDRAULIC CONTROL UNIT (EHCU) The EHCU contains six ABS solenoid valves, an isolation valve and a modulation valve for each of the three individual brake circuits. The EHCU also has a single pump motor that drives two separate pumps (one for the front brakes and the other for the rear brakes).

When did GMC add 4 wheel anti lock brakes?

In 1992, the four-wheel anti-lock braking system was added to the two-door S- and T-series trucks, Suburban, full-size Blazer/GMC Yukon, Geo Tracker and the limited-production GMC Typhoon. The 4WAL system is a nonintegral, four-wheel, three-channel ABS system with a conventional master cylinder and brake booster.

Is there a trick to bleeding the brakes on a 1998 Chev?

Press the brake pedal firmly and run the Scan Tool Automatic Bleed Procedure. Release the brake pedal between each test. Bleed all four wheels again using Steps 3-9. This will remove the remaining air from the brake system. Evaluate the feel of the brake pedal before attempting to drive the vehicle.

How do you Bleed an anti lock braking system?

This system can also be bled using a bi-directional scan tool. The process is usually called the “system function test.” This process opens the valves and cycles the pump to purge air from the hidden areas of the modulator and should be run three times to make sure all air is removed.

Is there a way to bleed the ebc4 system?

To bleed the EBC4 system use the following steps: Bleed the master cylinder before the BPMV (Brake Pressure Modulation Valve). The master cylinder can be bled through the brake lines. Loosen the line fitting at the secondary outlet and depress the brake pedal no more than 1/3 the distance.