Electronic Brake Control Module
The Electronic Brake Control Module (EBCM) is a small control computer, mounted under the dash to the left of the steering column, which monitors system operation and controls anti-lock function when required. The EBCM relies on inputs from the wheel speed sensors and hydraulic unit to determine if the ABS is operating properly and to determine when anti-lock control is required. When anti-lock mode is engaged, the EBCM produces output signals to the hydraulic unit for control and modulation of hydraulic pressure in the individual wheel circuits. EBCM inputs and outputs are shown in Fig 1 and are described below.
The EBCM continuously monitors the speed of each wheel to determine if any wheel is beginning to lock. If a wheel locking tendency is detected, the EBCM commands appropriate valve positions to modulate brake fluid pressure in some or all of the hydraulic circuits to prevent wheel lock-up and provide optimum braking. The EBCM continues to control pressure in individual hydraulic circuits until a locking tendency is no longer present.
The EBCM also has a self-diagnostic capability, including 16 trouble codes, which may be used in the event of a system malfunction. The EBCM can be requested to display these trouble codes (if any are present) by entering ABS diagnostic mode. See SELF-DIAGNOSTIC SYSTEM for further information. If the EBCM detects an error, it can disable the anti-lock function and/or turn on the Red BRAKE warning lamp in the instrument panel cluster.