EBCM (Electronic Brake Control Module) Description

EBCM (Electronic Brake Control Module) Description
The EBCM performs the following primary functions; order to provide efficient braking and vehicle stability. In DDRP system, Power to the Rear Hold Valve Solenoid is provided from Ignition. If the following fault conditions are existing, The Red Brake Warning Lamp will be illuminated.
^ Monitor wheel speed sensor inputs.
^ Detect wheel slip tendencies.
^ Control the brake system while in the antilock control mode.
^ Monitor the system for proper electrical operation.
The EBCM continuously checks the speed of each wheel to determine if any wheel is beginning to slip. If any wheel slip 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 slip and provide optimum braking. The EBCM continues to control pressure in individual hydraulic circuits until a slipping tendency is no longer present. Also the EBCM continuously monitors the ABS for proper operation. If the EBCM detects an error, it can disable the ABS function and turn on the ABS Warning Lamp in the instrument cluster. The EBCM also controls the display of the ABS Diagnostic Trouble Codes (DTCs) while in diagnostic mode.

Solenoid Relay
The solenoid relay, provides power to the pump motor and solenoids. The switch in the relay is normally open, but is commanded to close during initialization. The relay switch will remain closed for the remainder of the drive cycle as long as no Diagnostic Trouble Codes (DTCs) set which required the switch to open. If a DTC sets which requires the relay to be commanded off, battery voltage will be removed from the pump motor and solenoids for the remainder of the current drive cycle and ABS cannot function. The relay is an integral part of the EBCM and cannot be serviced separately.

Wheel Speed Sensors and Rings
A wheel speed sensor is present at each wheel. The sensors transmit wheel speed information to the EBCM by means of a small AC voltage. This voltage is generated by magnetic induction caused by passing a toothed sensor ring past a stationary sensor. The magnitude and frequency of the AC voltage are proportional to the speed of the wheel and both will increase with increasing speed. The signal is transmitted to the EBCM through interface that can cause false or noisy wheel speed sensor input to the EBCM. Two different types of wheel speed sensors are used for DBC 7 system.