Brake Pressure Modulator Valve Replacement

Fig 1: Brake Pressure Modulator Valve

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
CAUTION: Refer to Brake Fluid Irritant Caution . NOTE: Refer to Brake Fluid Effects on Paint and Electrical Components Notice . NOTE: Always connect or disconnect the wiring harness connector from the EBCM/EBTCM with the ignition switch in the OFF position. Failure to observe this precaution could result in damage to the EBCM/EBTCM. Preliminary Procedures Turn the ignition switch to the OFF position. Reposition the air cleaner outlet resonator forward slightly. Lift to release the resonator from the studs on the rail. Refer to Air Cleaner Outlet Resonator Replacement . Clean the electronic brake control module (EBCM) to brake pressure modulator valve (BPMV) area of any accumulated dirt and foreign material.
1	Connector, Electronic Brake Control Module (EBCM) Electrical Tip: Lift the EBCM electrical connector locking lever upward.
2	Fitting, Brake Pipe (Qty: 6) NOTE: Refer to Fastener Notice . Tighten:: 20 N.m (15 lb ft) Tip: Note the location of the brake pipe fittings for installation. Cap the brake pipe fittings to prevent brake fluid loss and contamination. Carefully position the brake pipes aside to provide access to remove the BPMV assembly.
3	Bolt, Brake Pressure Modulator Valve (BPMV) Bracket (Qty: 2) Tighten: 10 N.m (89 lb in)
4	Bolt, BPMV Bracket Tighten: 10 N.m (89 lb in) Tip: Loosen but do not remove the bolt.
5	Assembly, BPMV Tip: Plug the BPMV inlet and outlet ports to prevent brake fluid loss and contamination. Remove the BPMV to bracket mounting bolt. Tighten: 11 N.m (97 lb in) Do not pry against the accumulator covers on the underside of the brake pressure modulator assembly to release the mounting pins from the bracket insulators. Do not remove the mounting pins unless it is necessary to aid in releasing the modulator assembly from the bracket. Inspect the insulators and replace if necessary. If installing a new BPMV, remove the EBCM. Refer to Electronic Brake Control Module Replacement . A new BPMV comes with both the primary and secondary circuits pre-filled with brake fluid. As long as the ignition key has not been cycled after installation, only a base brake bleed is necessary. Bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Manual) or Hydraulic Brake System Bleeding (Pressure) . Perform the Diagnostic System Check - Vehicle . Observe brake pedal feel after performing the diagnostic system check. If the pedal now feels spongy, air may have been in, or may have been introduced into the secondary hydraulic circuit of the brake modulator which then may have been introduced into the primary circuit. If the pedal feels spongy, perform the Antilock Brake System Automated Bleed Procedure .