For 1990-2009 cars only
Two -- Person Procedure
Important:
• Use the two-person bleed procedure under the following conditions: - Installing a new Electro-Hydraulic Control Unit (EHCU) or new Brake Pressure Modulator Valve (BPMV). - Air is trapped in the valve body. • Do not drive the vehicle until the brake pedal feels firm. • Do not reuse brake fluid that is used during bleeding. • Use the vacuum, the pressure and the gravity bleeding procedures only for base brake bleeding.
- 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 GM approved brake fluid. Refer to Fluid and Lubricant Recommendations.
- Open the bleed screw 1/2 to 1 full turn.
- 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.
- Press the brake pedal firmly and run the Scan Tool Automated 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.
- Bleed the system as many times as necessary in order to obtain the appropriate feel of the pedal.
