Brake Pressure Modulator Valve (BPMV) is integral with Electronic Brake Control Module (EBCM) mounted on a bracket on power brake vacuum booster. See Fig 1 . The BPMV/EBCM monitors speed of each wheel to determine if a wheel is beginning to lock when brakes are applied. If a locking condition is detected, brake pressure is adjusted to that particular wheel to provide maximum braking without wheel lock.

BPMV/EBCM also monitors each input and output for proper operation. BPMV/EBCM will set a Diagnostic Trouble Code (DTC) if a system malfunction is detected.

The Brake Pressure Modulator Valve (BPMV) contains the Electronic Brake Control Module (EBCM), a solenoid valve for each brake channel, a flow control valve for each brake channel, buffer chambers, a pump motor and check valves. See Fig 2 .

During ABS stop, BPMV/EBCM activates solenoid valve for affected brake hydraulic channel. Solenoid valve triggers adjoining flow control valve which directs hydraulic pressure into a buffer chamber. The result is a reduction in hydraulic pressure at the wheel brake, reducing wheel slip. When wheel is no longer slipping, BPMV/EBCM deactivates solenoid valve. This allows flow control valve to increase hydraulic pressure at wheel brake. This action continues for all wheels until wheels are no longer slipping.

Fig 1: BPMV/EBCM Assembly

Courtesy of GENERAL MOTORS CORP.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Brake Pressure Modulator Valve/Electronic Brake Control Module(BPMV/EBCM)

Use the Manual With the Right Hardware

When to See a Mechanic