Electronic Brake Control Module/Brake Pressure Modulator Valve (EBCM/BPMV)
Electronic Brake Control Module (EBCM) is integral with Brake Pressure Modulator Valve (BPMV) mounted on a bracket on power brake vacuum booster. See Fig 1 . The 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 for maximum braking without wheel lock.
EBCM also monitors each input and output for proper operation. EBCM will set a Diagnostic Trouble Code (DTC) if a system malfunction is detected.
The Brake Pressure Modulator Valve (BPMV) contains the 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, 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, 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.