Sierra 1500 4WD V8-5.3L VIN Z Flex Fuel (2005)
22. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
23. Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be driven until it is diagnosed and repaired.
If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.