The ABS VI Antilock Braking System consists of the following components:

The conventional brake system includes the following components:

The ABS VI includes the following components:

The ABS Brake Modulator/Motor Pack Assembly controls hydraulic pressure to the following areas:

The ABS Brake Modulator/Motor Pack Assembly controls hydraulic pressure by modulating the hydraulic pressure. This action prevents wheel slip.

The basic ABS brake modulator configuration consists of the following components:

The ABS brake motor pack consists of the following components:

Refer to Base Brake System and Antilock Brake System in this section for more information.

Notice: There is no serviceable or removable PROM. The EBCM/EBTCM must be replaced as an assembly.

The Electronic Brake Control Module (EBCM) controls the ABS VI. A microprocessor controls the EBCM.

The inputs to the system include the following components:

The outputs include the following components:

A serial data line is provided for service diagnostic tools and assembly plant testing.

The EBCM monitors the speed of each wheel.

The EBCM controls the motors and the solenoids in order to reduce brake pressure to a particular wheel when the following conditions exist:

When the wheel regains traction, brake pressure increases until the wheel approaches slip again.

This cycle will repeat until one of the following conditions exists:

Refer to Self-Diagnostics for more information.

The front wheel speed sensors are of a variable reluctance type. Each sensor is attached to the knuckle assembly in close proximity to a toothed ring. The toothed ring is pressed onto the outer Constant Velocity (CV) joint. An AC voltage is generated when the toothed ring passes by the sensor. The magnitude and frequency are proportional to the speed of the wheel and both will increase with increasing speed.

The sensor is not repairable.

The air gap is not adjustable.

The rear wheel speed sensors operate in the same manner as the front wheel speed sensors.

The rear wheel speed sensors are mounted in the rear suspension knuckles. The rear wheel speed sensor reluctor ring is part of the rear hub and bearing assembly.

The sensor and the toothed ring are not repairable.

The air gap cannot be adjusted.

The entire integral bearing and speed sensor unit must be replaced if a rear wheel speed sensor fails.

The Electronic Brake Control Relay is a normally-open contact type.

The Electronic Brake Control Relay has special contact material to handle the high currents required for the ABS VI operation.

The relay allows battery voltage and current to be supplied to the EBCM and solenoids. The EBCM supplies power to the motors.

The wiring harness is the mechanism which electrically connects the EBCM to the following components:

The wiring harness consists of the following components:

A jumper harness located between each wheel speed sensor and the main wiring harness.

Each jumper harness is made of highly flexible twisted pair wiring.

The wiring exists because the main harness must connect to the suspension of the vehicle. Therefore, the wiring in this area is subjected to the same motion as a spring or a shock absorber. Any repair to this section of wiring will result in stiffening. Stiffening will eventually result in failure due to wire fatigue.

The wheel speed sensor jumper harnesses are not repairable and must be replaced. Do not attempt to solder, splice, or crimp the harnesses. Eventual failure will occur.

Refer to Wheel Speed Sensor Jumper Harness Replacement (Front) and Wheel Speed Sensor Jumper Harness Replacement (Rear) .

The Electronic Brake Control Module (EBCM) continuously monitors itself and other ABS components.

If the EBCM detects a problem with the system, the amber ABS warning indicator will light continuously (solid indicator) in order to alert the driver of the problem.

The amber ABS warning indicator flashes to warn the driver of an existing ABS malfunction which may have degraded the base brake performance. In this situation, the vehicle must be serviced immediately in order to regain full base and ABS operation.

A solid amber ABS warning indicator indicates that a problem has been detected. The problem is one that affects the operation of the ABS. In this situation, no antilock braking will be available. Normal (non-antilock) brake performance will still be available.

The ABS VI must be serviced in order to regain ABS braking ability.

ABS Active Indicator

Since brake pedal feedback normally associated with ABS operation does not occur with ABS-VI, there is an additional indicator in the instrument cluster to inform the driver of ABS operation. The blue ABS ACTIVE indicator will illuminate during an ABS event and during system initialization.

Brake Warning Indicator

The red BRAKE warning indicator illuminates when the following conditions exist:

The EBCM will illuminate the red BRAKE warning indicator when an ABS fault could interfere with base brake operation.

When this type of fault is detected, the EBCM will store the appropriate DTC and disable ABS.

The power distribution system of the vehicle consists of the fuses and the ignition switch. The fuses are as follows: