ABS System Components Description

The MGH-25 Antilock Brake System (ABS) consists of a conventional hydraulic brake system plus antilock components. The conventional brake system includes a vacuum booster, master cylinder, front disc brakes, rear drum brakes, interconnecting hydraulic brake pipes and hoses, brake fluid level sensor and the brake warning lamp indicator.

The ABS components include a hydraulic unit, an EBCM (Electronic Brake Control Module), system fuse, 4 wheel speed sensor (one at each wheel), interconnecting wiring, ABS indicator, the DDRP (De-coupled Dynamic Rear Proportioning) indicator (which is connected to the parking lamp) and the rear drum brakes. See Component Location  for the general layout of this system.

The hydraulic unit with the attached EBCM is located between the surge tank and the fire wall on the left side of the vehicle.

The basic hydraulic unit configuration consists of hydraulic check valves, 2 solenoid valves for each wheel, a hydraulic pump, 2 accumulators. The hydraulic unit controls hydraulic pressure to the front calipers and the rear wheel cylinders by modulating hydraulic pressure to prevent wheel lockup.