Electronic Brake Control Module: Description and Operation

Purpose:
The Electronic Brake and Traction Control Module (EBTCM) receives various inputs from the PCM, wheel speed sensors and TPS module. It outputs information to various devices such as the PCM, modulator valve assembly and adjuster assembly.

The EBTCM determines when to actuate the Acceleration Slip Regulation (ASR) system and how to do so for the particular situation requiring ASR response. ASR intervention can be done by using one or a combination of the following methods:

^ Timing retard
^ Throttle close-down
^ Brake intervention

The EBTCM receives engine rpm information from the tach filter circuit. This information is considered by the EBTCM in ignition retard control.

The EBTCM controls the amount of adjuster assembly output, controlling the amount and rate at which the throttle is moved toward the closed-throttle position.

The EBTCM can, if necessary, direct the modulator valve assembly to increase, hold or relieve brake pressure to individual wheels to assist in maintaining directional stability and vehicle control.

The EBTCM also will disable the ASR system in the event the engine is not running with the ignition "ON", such as what may occur if the vehicle is being towed.

Operation:
The EBTCM sends a retard spark signal to the PCM interface. However, the spark retard is limited to TDC, even if the request could reduce spark timing to a point after TDC. This is done to help control catalytic converter temperature, as well as driver perception of engine "feel". The ignition retard signal is based on engine rpm.

Location:
The EBTCM is located in the rear storage compartment directly behind the driver's seat.