Dump and Isolation Valve Testing
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 EBCM automatically de-energizes the solenoid after about 5 seconds. When this occurs, verify that the brake pedal drops about 2.2 cm (1 inch).