Dump and Isolation Valve Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
Pressure Dump Test Procedure
- Apply the parking brake fully.
- Start the engine and allow the engine to idle.
- Select the desired Dump Valve Solenoid Test on the scan tool.
- Apply the brake and maintain steady pressure on the brake pedal.
- Command the solenoid ON and verify that the brake pedal drops to the floor.
Wheel Isolation Test Procedure
- Apply the parking brake fully.
- Start the engine and allow the engine to idle.
- Select the desired Isolation Valve Solenoid Test on the scan tool.
- Apply the brake with very light pressure, only enough to open the brake switch.
- Command the solenoid ON and then immediately apply firm and steady pressure to the brake pedal.
- The electronic brake control module (EBCM) automatically de-energizes the solenoid after about 5 seconds. When this occurs, verify that the brake pedal drops about 2.2 cm (1 in).