2004 Cadillac Escalade EXT Brake Master Cylinder

You need to install the fluid level sensor until the locking tabs snap into place, and connect the electrical connector to the fluid level sensor.

You need to disconnect the electrical connector from the fluid level sensor, compress the locking tabs at the opposite side of the master cylinder, and remove the fluid level sensor.

When adding fluid to the brake master cylinder reservoir, you should use only Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.

You need to remove the brake master cylinder from the vehicle, secure the mounting flange of the brake master cylinder in a bench vise, clean the outside of the master cylinder reservoir on and around the reservoir cap prior to removing the cap and diaphragm and remove the reservoir cap and diaphragm from the reservoir. You also need to inspect the reservoir cap and diaphragm, remove the master cylinder reservoir from the master cylinder, depress the primary piston, remove the piston retainer and primary piston assembly from the cylinder bore, plug the cylinder inlet ports and the rear outlet port, apply low pressure, non-lubricated, filtered air into the front outlet port and discard the primary piston assembly, the piston retainer, and the seals and seal retainer from the secondary piston.

When the reservoir cap and diaphragm have cuts or cracks, or nicks or deformation.