Electronic Brake Control Module: Description and Operation

DESCRIPTION
The Anti-lock Brake control module;
^ is located below the brake pressure control valve block.
^ is an on-board diagnostic non-repairable unit consisting of two microprocessors and the necessary circuitry for their operation.
^ The anti-lock brake control module monitors system operation during normal driving, anti-lock braking, and, if equipped, traction control cycling.

OPERATION
^ Under normal driving conditions, the microprocessors produce short test pulses to the solenoid valves that check the electrical system without any mechanical reaction.
^ Impending wheel lock conditions trigger signals from the anti-lock brake control module that open and close the appropriate solenoid valves.
^ When the pump motor starts to run, the driver may hear some noise and will feel moderate pulsations in the brake pedal.
^ During normal braking, the brake pedal feel will be identical to a standard brake system.

TRACTION CONTROL OPERATION
During traction control operation, the anti-lock brake control module operates as follows:
^ During acceleration, if one or both rear wheels lose traction or begin to spin, the anti-lock brake control module will close the isolation valves and operate the pump motor. If the driver applies the brakes during cycling, the system will automatically shut off
^ The anti-lock brake control module monitors traction control usage and will shut off the traction control features to prevent overheating of the rear brakes.
^ If the system shuts off, there is a cool-down period required before it becomes functional again. This period varies depending on brake usage during the cool-down period.
^ Anti-lock braking is still fully functional during the cool-down period.

TROUBLE CODES (DTC)
Most malfunctions which occur to the anti-lock brake system and the traction control will be stored as a diagnostic trouble code (DTC) in the keep-alive memory of the anti-lock brake control module. DTCs can be retrieved by following the on-board diagnostic (OBD)procedures. Refer to Powertrain Management, or refer to Scan tool manufacturers instructions.