Electronic Brake Control Module (EBCM)

DESCRIPTION
The controlling element of ABS VI is a microprocessor based Electronic Brake Control Module, or EBCM. Inputs to the system include four wheel speed sensors, the stoplamp switch, ignition switch, and unswitched battery voltage. Outputs include three bi-directional motor controls, two solenoid controls, the ABS relay and the lamp driver relay. A serial data line is used for service diagnostic tools (Tech 2 scan tool), assembly plant testing. The EBCM monitors the speed of each wheel.


OPERATION
If any wheel begins to approach lock-up, the EBCM controls the motors and solenoids to reduce brake pressure to the wheel approaching lock-up. Once the wheel regains traction, brake pressure is increased until the wheel again begins to approach lock-up. This cycle repeats until either the vehicle comes to a stop; the brake is released, or no wheels approach lock-up. Additionally, the EBCM monitors itself; each input and each output for proper operation. If any system malfunction is detected, the EBCM will store a DTC in nonvolatile memory (DTCs will not disappear if the battery is disconnected). Refer to Self-Diagnostics in this section for more detailed information. The EBCM is located inside the left side of the I/P, above the junction block.