Ford Scorpio, Galaxy, Maverick, Fiesta, Escourt, Mondeo ABS : general information

Anti-lock Braking System

The electronic Anti-lock Braking System is made up of a conventional brake system with split 
dual-circuits and an ABS actuator. The ABS actuator for all vehicles except Maverick consists 
of the following components:
- Hydraulic actuator.
- ABS brake pressure pump.
- ABS module .
The Maverick ABS actuator consists of the following components:
- Hydraulic actuator.
- ABS brake pressure pump.
Four wheel sensors supply the wheel-speed signals required for control. These signals are 
compared by the ABS module with physical limiting values stored in the ABS module.
During braking if the wheel speed of one or more of the wheels approaches the locking limit, 
the ABS module activates the corresponding ABS solenoid valve. This leads to a drop in 
brake pressure in the respective brake cylinder. If the wheel speed now exceeds the locking 
limit, the ABS control module switches on the brake pressure. The pressure in the wheel 
cylinder assembly is rapidly increased by the ABS brake pressure pump according to the brake 
pressure applied by means of the brake pedal. During the pressure build-up phase the ABS 
solenoid valves are deactivated. Depending on the condition of the road surface and the length 
of time of the braking procedure this procedure can be repeated many times per second, and is 
called the ABS control frequency. The maximum control frequency of the ABS system is 
approximately 20 Hz.
ABS control is not active at road speeds of less than 5 km/h (3 mph). The '96 Fiesta fitted with 
the electronic brake force feature is a new part of the integrated system that limits the slip of the 
rear wheels before the anti-lock braking system comes into effect. By comparing the slip of the 
front and rear wheels, the system optimizes the brake distribution for maximum driver control 
regardless of vehicle loading.Due to the system automatically compensating for all conditions of 
vehicle loading, there is no need for a load apportioning valve. 

          

ABS/TCS Pump

The ABS/TCS pump has been designed as a twin-piston pump; which means that two separate 
pump elements keep up the pressure level during ABS and TCS control. With each pump element 
supplying eithere a diagonal or front/rear brake circuit with the pressure required for ABS/TCS 
control. Therefore the ABS/TCS control still works in the remaining brake circuit, if a diagonal or 
front/rear circuit fails.

ABS/TCS Module (All vehicles except Maverick)

The ABS/TCS module is mounted on the hydraulic actuator. Two different ABS modules are used 
in certain models:
· ABS module
· ABS/TCS module
The two control units are all most identical in operational stratergy and design. Only difference 
externally is their part numbers. There are two different microprocessors controlling the program 
sequence. One of the microprocessors provides mostly a monitoring function the other controlling the 
ABS system. The relay in the ABS/TCS module activates the ABS brake pressure pump and in this 
way the ABS brake pressure pump is supplied with voltage. When voltage peaks occur the diodes 
integrated in the relay assembly protect against polarity reversal and over-voltage.

Fig 1 Scorpio & Galaxy ABS/TCS module
Ford Scorpio, Galaxy, Maverick, Fiesta, Escourt, Mondeo ABS : general information Fig.2 96 Fiesta& 96 Escort TCS/ABS module Ford Scorpio, Galaxy, Maverick, Fiesta, Escourt, Mondeo ABS : general information Fig.3 Mondeo ABS/TCS module